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B 3.1.7 Rod Position Indication | B 3.1.7 Rod Position Indication | ||
BASES USAR, Section 7.1 BACKGROUND According to GDC 13 (Ref. 1), instrumentation to monitor variables and systems over their operating ranges during normal operation, anticipated operational occurrences, and accident conditions must be OPERABLE. LCO 3.1.7 is required to ensure OPERABILITY of the control rod position indicators to determine control rod positions and thereby ensure compliance with the control rod alignment and insertion limits. INSERT 1 1 6 The OPERABILITY, including position indication, 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. Rod position indication is required to assess OPERABILITY and misalignment. | BASES USAR, Section | ||
==7.1 BACKGROUND== | |||
According to GDC 13 (Ref. 1), instrumentation to monitor variables and systems over their operating ranges during normal operation, anticipated operational occurrences, and accident conditions must be OPERABLE. LCO 3.1.7 is required to ensure OPERABILITY of the control rod position indicators to determine control rod positions and thereby ensure compliance with the control rod alignment and insertion limits. INSERT 1 1 6 The OPERABILITY, including position indication, 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. Rod position indication is required to assess OPERABILITY and misalignment. | |||
Mechanical or electrical failures may cause a control rod to become inoperable or to become misaligned from its group. Control 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. | Mechanical or electrical failures may cause a control rod to become inoperable or to become misaligned from its group. Control 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. |
Revision as of 08:11, 9 February 2019
ML101890212 | |
Person / Time | |
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Site: | Kewaunee |
Issue date: | 07/01/2010 |
From: | Dominion Energy Kewaunee |
To: | Office of Nuclear Reactor Regulation |
References | |
Download: ML101890212 (214) | |
Text
Summary of Changes ITS Section 3.1 Page 1 of 1 Change Description Affected Pages The changes described in the KPS response to question RPG-006 have been made. This change corrects a cross reference to another LCO requirement. Pages 181, 186, 190, and 199
ATTACHMENT 1 VOLUME 6 KEWAUNEE POWER STATION IMPROVED TECHNICAL SPECIFICATIONS CONVERSION ITS SECTION 3.1 REACTIVITY CONTROL SYSTEMS
Revision 1
LIST OF ATTACHMENTS
- 1. ITS 3.1.1
- 2. ITS 3.1.2
- 3. ITS 3.1.3
- 4. ITS 3.1.4
- 5. ITS 3.1.5
- 6. ITS 3.1.6
- 7. ITS 3.1.7
- 8. ITS 3.1.8
- 9. Relocated/Deleted Current Technical Specifications (CTS)
ATTACHMENT 1 ITS 3.1.1, SHUTDOWN MARGIN Current Technical Specification (CTS) Markup and Discussion of Changes (DOCs)
A01 ITS 3.1.1 ITS 3.10 CONTROL ROD AND POWER DISTRIBUTION LIMITS APPLICABILITY Applies to the limits on core fission power distributions and to the limits on control rod operations.
OBJECTIVE To ensure: 1) core subcriticality after reactor trip, 2) acceptable core power distribution during power operation in order to maintain fuel integrity in normal operation transients
associated with faults of moderate frequency, supplemented by automatic protection and by administrative procedures, and to maintain the design basis initial conditions for limiting faults, and 3) limited potential reactivity insertions caused by hypothetical control rod
ejection.
SPECIFICATION
- a. Shutdown Reactivity
When the reactor is subcritical prior to reactor startup, the SHUTDOWN MARGIN shall be at
least that as specified in the COLR
- b. Power Distribution Limits
- 1. At all times, except during Low Power Physics Tests, the hot channel factors defined in the basis must meet the following limits:
A. F Q N (Z) Limits shall be as specified in the COLR.
B. FH N Limits shall be as specified in the COLR.
- 2. If FH N not within limits:
A. Perform the following:
- i. Within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> either, restore FH N to within its limit or reduce thermal power to less than 50% of RATED POWER.
ii. Reduce the Power Range Neutron Flux-High Trip Setpoint to 55% of RATED POWER within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
iii. Verify FH N within limits within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
B. If the actions of TS 3.10.b.2.A are not completed within the specified time, then reduce thermal power to 5% of rated power within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
A pplicabilit y A02M01Add proposed ACTION A LCO 3.1.1 See ITS 3.2.1 and 3.2.2 See ITS 3.2.2 See ITS 3.2.1 Amendment No. 167 TS 3.10-1 04/04/2003 Page 1 of 3 A01ITS ITS 3.1.1 4.1 OPERATIONAL SAFETY REVIEW APPLICABILITY Applies to items directly related to safety limits and LIMITING CONDITIONS FOR OPERATION.
OBJECTIVE To assure that instrumentation shall be checked, tested, and calibrated, and that equipment and sampling tests shall be conducted at sufficiently frequent intervals to
ensure safe operation.
SPECIFICATION
- a. Calibration, testing, and checking of protective instrumentation channels and testing of logic channels shall be performed as specified in Table TS 4.1-1.
- b. Equipment and sampling tests shall be conducted as specified in Table TS 4.1-2 and TS 4.1-3.
- c. Deleted
- d. Deleted
- e. Deleted See otherITS SR 3.1.1.1 Amendment No. 119 TS 4.1-1 04/18/95 Page 2 of 3 A01 ITS 3.1.1 ITS TABLE TS 4.1-2 MINIMUM FREQUENCIES FOR SAMPLING TESTS Amendment No. 119 Page 1 of 2 04/18/95 SAMPLING TESTS TEST FREQUENCY 1. Reactor Coolant Samples a. Gross Radioactivity Determination (excluding tritium) 5/week (1) b. DOSE EQUIVALENT I-131 Concentration 1/14 days (2) c. Tritium activity Monthly d. Chemistry (Cl, F, O 2)(3) 3/week (4)e. Determination 1/6 months (5) f. RCS isotopic analysis for Iodine Once per 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> in accordance with TS 3.1.c.2.C. 2. Reactor Coolant Boron (6) Boron Concentration (3) (3) 2/week 2/week (1) Maximum time between tests is 3 days.
(2) Sample required only when in the OPERATING MODE.
(3) Test required in all plant modes.
(4) Maximum time between tests is 4 days.
(5) Sample after a minimum of 2 EFPD and 20 days of OPERATING MODE operation have elapsed since the reactor was last subcritical f or 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.
(6) A reactor coolant boron concentration sample does not have to be taken when the core is completely unloaded. Add proposed SR 3.1.1.1 See ITS 3.4.16 See ITS 3.4.16 M02 See CTS 3.1.e A02 L01 See CTS 3.1.e See ITS 3.9.1 M02 LA01 Page 3 of 3 DISCUSSION OF CHANGES ITS 3.1.1, SHUTDOWN MARGIN (SDM)
ADMINISTRATIVE CHANGES A01 In the conversion of the Kewaunee Current Technical Specifications (CTS) to the plant specific Improved Technical Specifications (ITS), certain changes (wording preferences, editorial changes, reformatting, revised numbering, etc.) are made to obtain consistency with NUREG-1431, Rev. 3.0, "Standard Technical Specifications-Westinghouse Plants" (ISTS).
These changes are designated as administrative changes and are acceptable because they do not result in technical changes to the CTS.
A02 CTS 3.10.a states that when the reactor is subcritical prior to startup, the SHUTDOWN MARGIN (SDM) shall be at least that as specified in the COLR. CTS Table 4.1-2 Sampling Test 2 footnote (3) states that the boron concentration test is required in all plant modes. ITS 3.1.1 is applicable in MODE 2 with k eff < 1.0 and in MODES 3, 4, and 5. This changes the CTS by specifically stating that the applicability is in MODE 2 with k eff < 1.0 and in MODES 3, 4, and 5. The change in Applicability for MODE 1 and MODE 2 with k eff 1.0 is discussed in DOC L01. In MODE 6, the reactor head is detensioned or removed, so a reactor startup cannot occur. In addition, ITS 3.9.1 provides the MODE 6 boron concentration limits.
This change is acceptable because the applicability has not changed. This change results in a format change only to comply with the ISTS presentation of the Applicability. The purpose of CTS Table 4.1-2 Sampling Test 2 is to verify that the boron concentration is within limits to satisfy the SDM. In MODE 2 with
k eff < 1.0 and in MODES 3, 4, and 5 the boron concentration is taken into consideration as part of the reactivity balance calculation required in ITS SR 3.1.1.1. The deletion of the MODE 1 and MODE 2 with k eff > 1.0 is discussed in DOC L01 and the MODE 6 requirement is covered in ITS 3.9.1.
Therefore, the change is acceptable because the boron concentration
requirements have not changed. This change is designated as an administrative change since it does not result in any technical changes to the CTS.
MORE RESTRICTIVE CHANGES
M01 CTS 3.10.a does not supply any explicit time to restore the SDM to within limits when the SDM is not within its limit. As a result, LCO 3.0.c would be entered, which requires action to be initiated within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and to place the unit in HOT
STANDBY (equivalent to ITS MODE 2) within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, in HOT SHUTDOWN (equivalent to ITS MODE 3) within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and in COLD SHUTDOWN (equivalent to ITS MODE 5) within the subsequent 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />.
Under similar conditions, ITS 3.1.1 provides 15 minutes to initiate boration to restore SDM to within limits. This changes the CTS by providing a maximum time limit of 15 minutes to initiate boration to restore SDM to within limits prior to
The purpose of CTS 3.10.a SDM requirements is to provide sufficient reactivity margin to ensure that fuel design limits will not be exceeded for normal shutdown and anticipated operational occurrences (AOOs). This change is acceptable Kewaunee Power Station Page 1 of 3 DISCUSSION OF CHANGES ITS 3.1.1, SHUTDOWN MARGIN (SDM) because the Completion Time is consistent with safe operation under the specified Condition, considering the operability status of the redundant systems of required features, the capacity and capability of remaining features, a reasonable time for repairs or replacement of required features, and the low probability of a DBA occurring during the allowed Completion Time. The ITS 3.1.1 Completion Time of 15 minutes is adequate for an operator to correctly align and start the required systems and components. In addition, the ITS Bases for the ACTION states that boration must be initiated promptly. The current action (LCO 3.0.c) allows up to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> to start adding negative reactivity. The proposed action requires negative reactivity addition to begin in 15 minutes, and to continue until SDM is restored. This change is designated as more restrictive because a shorter time is allowed in ITS to restore parameters to within the LCO limits than was allowed in the CTS.
M02 CTS 3.10.a does not provide any Surveillance Requirements for verifying that the SDM is within the limits specified in the COLR. CTS Table 4.1-2 provides one parameter of the SDM in the boron concentration test which is performed two times per week. ITS SR 3.1.1.1 requires verifying that the SDM is within the limits specified in the COLR every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. This changes the CTS by adding a new Surveillance Requirement to verify the SDM.
This change is acceptable because the added Surveillance Requirement proves that the SDM requirements are being met. Furthermore, the boron concentration test is a portion of the reactivity effects that are necessary to perform a reactivity balance calculation but is not included in the reactivity balance calculation. In addition to the RCS boron concentration, the control bank position, RCS average temperature, fuel burnup based on gross thermal energy generation, xenon concentration, samarium concentration and isothermal temperature must be taken into account in the performance of the reactivity balance calculation. This change is designated as more restrictive because a new Surveillance Requirement is being added that was not specified in the CTS.
RELOCATED SPECIFICATIONS None
REMOVED DETAIL CHANGES LA01 (Type 3 - Removing Procedural Details for Meeting TS Requirements or Reporting Requirements) CTS Table 4.1-2 Sampling Test 2 requires sampling tests of RCS boron concentration. ITS 3.1.1 does not have a specific requirement to test RCS boron concentration. This changes the CTS by removing the details of the RCS boron concentration test to the Bases.
The removal of these details for performing Surveillance Requirement from the Technical Specification is acceptable since this type of information is not necessary to be included in the Technical Specifications to provide adequate protection of public health and safety. In ITS 3.1.1, RCS boron concentration is a parameter, in addition to control bank position, RCS average temperature, fuel Kewaunee Power Station Page 2 of 3 DISCUSSION OF CHANGES ITS 3.1.1, SHUTDOWN MARGIN (SDM)
Kewaunee Power Station Page 3 of 3 burnup based on gross thermal energy generation, xenon concentration, samarium concentration and isothermal temperature, used in performing the reactivity balance calculation. Therefore, the details of how SDM is calculated do not need to appear in the Specification in order for the requirement to apply.
Also, this change is acceptable because these types of procedural details will be adequately controlled in the ITS Bases. Changes to the Bases are controlled by the Technical Specifications Bases Control Program in Chapter 5. This change is designated as a less restrictive removal of detail change because procedural details for meeting Technical Specification requirements are being removed from the Technical Specifications.
LESS RESTRICTIVE CHANGES
L01 (Category 5 - Deletion of Surveillance Requirement)
CTS Table TS 4.1-2 Sampling Test 2, footnote (3) states that the boron concentration test is required in all plant modes. ITS 3.1.1 is applicable in MODE 2 with k eff < 1.0 and in MODES 3, 4, and 5. This changes CTS by not requiring the boron concentration test in MODE 1 and MODE 2 with k eff 1.0. ITS 3.9.1 provides the MODE 6 boron concentration limits.
The purpose of CTS Table TS 4.1-2, Sampling Test 2 is to verify the boron concentration. When the reactor is critical (MODE 1 and MODE 2 with k eff 1.0), SDM is verified by ensuring that the control rods are within the insertion limits (see ITS 3.1.5 and ITS 3.1.6). If the control banks are not within their insertion limits in MODE 1 and MODE 2 with k eff 1.0, ITS 3.1.6, Required Action A.1.1 and B.1.1 require the SDM to be verified within limits. This requires performing a reactivity balance calculation considering Reactor Coolant System (RCS) boron concentration, control bank position, RCS average temperature, fuel burnup based on gross thermal energy generation, xenon concentration, samarium concentration and isothermal temperature. Therefore, the boron concentration sampling test is not needed in MODE 1 and MODE 2 with k eff 1.0. This change has been designated as less restrictive because a Surveillance that was required in CTS is no longer required in ITS.
Improved Standard Technical Specifications (ISTS) Markup and Justification for Deviations (JFDs)
SDM 3.1.1 WOG STS 3.1.1-1 Rev. 3.0, 03/31/04 CTS 3.1 REACTIVITY CONTROL SYSTEMS
3.1.1 SHUTDOWN
MARGIN (SDM)
LCO 3.1.1 SDM shall be within the limits specified in the COLR.
3.10.a
APPLICABILITY: MODE 2 with k eff < 1.0, 3.10.a MODES 3, 4, and 5.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME
A. SDM not within limits.
A.1 Initiate boration to restore SDM to within limits.
15 minutes DOC M01 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY
SR 3.1.1.1 Verify SDM to be within the limits specified in the COLR.
24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> DOC M02 JUSTIFICATION FOR DEVIATIONS ITS 3.1.1, SHUTDOWN MARGIN (SDM)
None Kewaunee Power Station Page 1 of 1 Improved Standard Technical Specifications (ISTS) Bases Markup and Bases Justification for Deviations (JFDs)
SDM B 3.1.1 WOG STS B 3.1.1-1 Rev. 3.0, 03/31/04 B 3.1 REACTIVITY CONTROL SYSTEMS
B 3.1.1 SHUTDOWN MARGIN (SDM)
BASES BACKGROUND According to GDC 26 (Ref. 1), the reactivity control systems must be redundant and capable of holding the reactor core subcritical when shut down under cold conditions. Maintenance of the SDM ensures that postulated reactivity events will not damage the fuel.
8INSERT 1 SDM requirements provide sufficient reactivity margin to ensure that acceptable fuel design limits will not be exceeded for normal shutdown and anticipated operational occurrences (AOOs). As such, the SDM defines the degree of subcriticality that would be obtained immediately following the insertion or scram of all shutdown and control rods, assuming that the single rod cluster assembly of highest reactivity worth is fully withdrawn.
1control (RCCA)
The system design requires that two independent reactivity control systems be provided, and that one of these systems be capable of maintaining the core subcritical under cold conditions. These requirements are provided by the use of movable control assemblies and soluble boric acid in the Reactor Coolant System (RCS). The Control Rod System can compensate for the reactivity effects of the fuel and water temperature changes accompanying power level changes over the range from full load to no load. In addition, the Control Rod System, together with the boration system, provides the SDM during power operation and is capable of making the core subcritical rapidly enough to prevent exceeding acceptable fuel damage limits, assuming that the rod of highest reactivity worth remains fully withdrawn. The soluble boron system can compensate for fuel depletion during operation and all xenon burnout reactivity changes and maintain the reactor subcritical under cold conditions.
8INSERT 2 During power operation, SDM control is ensured by operating with the shutdown banks fully withdrawn and the control banks within the limits of LCO 3.1.6, "Control Bank Insertion Limits." When the unit is in the shutdown and refueling modes, the SDM requirements are met by means of adjustments to the RCS boron concentration.
APPLICABLE The minimum required SDM is assumed as an initial condition in safety SAFETY analyses. The safety analysis (Ref. 2) establishes an SDM that ensures ANALYSES specified acceptable fuel design limits are not exceeded for normal operation and AOOs, with the assumption of the highest worth rod stuck out on scram. For MODE 5, the primary safety analysis that relies on the SDM limits is the boron dilution analysis.
9(which includes reactor safety analyses not in USAR Chapter 14) 10 B 3.1.1 8 INSERT 1 Two independent reactivity control systems, preferably from different principles, shall be provided (Ref. 1). The reactivity control systems shall be capable of making and holding the core sub-critical from any hot standby or hot operating condition (Ref. 2).
8 INSERT 2 Furthermore, USAR GDC 30, "Reactivity Holddown Capability," requires that the reactivity control system provided shall be capable of making the core subcritical under credible accident conditions with appropriate margins for contingencies and limiting any subsequent return to power such that there will be no undue risk to the health and safety of the public (Ref. 3).
Insert Page B 3.1.1-1 SDM B 3.1.1 WOG STS B 3.1.1-2 Rev. 3.0, 03/31/04 BASES APPLICABLE SAFETY ANALYSES (continued)
The acceptance criteria for the SDM requirements are that specified acceptable fuel design limits are maintained. This is done by ensuring that:
- a. The reactor can be made subcritical from all operating conditions, transients, and Design Basis Events, 2
- b. The reactivity transients associated with postulated accident conditions are controllable within acceptable limits (departure from nucleate boiling ratio (DNBR), fuel centerline temperature limits for
AOOs, and 280 cal/gm energy deposition for the rod ejection accident), and
- c. The reactor will be maintained sufficiently subcritical to preclude inadvertent criticality in the shutdown condition.
The most limiting accident for the SDM requirements is based on a main steam line break (MSLB), as described in the accident analysis (Ref. 2). The increased steam flow resulting from a pipe break in the main steam system causes an increased energy removal from the affected steam generator (SG), and consequently the RCS. This results in a reduction of the reactor coolant temperature. The resultant coolant shrinkage causes a reduction in pressure. In the presence of a negative moderator temperature coefficient, this cooldown causes an increase in core reactivity. As RCS temperature decreases, the severity of an MSLB decreases until the MODE 5 value is reached. The most limiting MSLB, with respect to potential fuel damage before a reactor trip occurs, is a guillotine break of a main steam line inside containment initiated at the end of core life. The positive reactivity addition from the moderator temperature decrease will terminate when the affected SG boils dry, thus terminating RCS heat removal and cooldown. Following the MSLB, a post trip return to power may occur; however, no fuel damage occurs as a result of the post trip return to power, and THERMAL POWER does not violate the Safety Limit (SL) requirement of SL 2.1.1.
In addition to the limiting MSLB transient, the SDM requirement must also protect against:
- a. Inadvertent boron dilution, b. An uncontrolled rod withdrawal from subcritical or low power condition, ;; 200; 2 1 1 4 2 2; and SDM B 3.1.1 WOG STS B 3.1.1-3 Rev. 3.0, 03/31/04 BASES APPLICABLE SAFETY ANALYSES (continued)
- c. Startup of an inactive reactor coolant pump (RCP), and 3 d. Rod ejection.
c Each of these events is discussed below.
In the boron dilution analysis, the required SDM defines the reactivity difference between an initial subcritical boron concentration and the corresponding critical boron concentration. These values, in conjunction with the configuration of the RCS and the assumed dilution flow rate, directly affect the results of the analysis. This event is most limiting at the beginning of core life, when critical boron concentrations are highest.
Depending on the system initial conditions and reactivity insertion rate, the uncontrolled rod withdrawal transient is terminated by either a high power level trip or a high pressurizer pressure trip. In all cases, power level, RCS pressure, linear heat rate, and the DNBR do not exceed allowable limits.
The startup of an inactive RCP will not result in a "cold water" criticality, even if the maximum difference in temperature exists between the SG and the core. The maximum positive reactivity addition that can occur due to an inadvertent RCP start is less than half the minimum required SDM. Startup of an idle RCP cannot, therefore, produce a return to power from the hot standby condition.
The ejection of a control rod rapidly adds reactivity to the reactor core, causing both the core power level and heat flux to increase with corresponding increases in reactor coolant temperatures and pressure. The ejection of a rod also produces a time dependent redistribution of
core power.
SDM satisfies Criterion 2 of 10 CFR 50.36(c)(2)(ii). Even though it is not directly observed from the control room, SDM is considered an initial condition process variable because it is periodically monitored to ensure that the unit is operating within the bounds of accident analysis assumptions.
LCO SDM is a core design condition that can be ensured during operation through control rod positioning (control and shutdown banks) and through the soluble boron concentration.
3 4an overtemperature T 1 SDM B 3.1.1 WOG STS B 3.1.1-4 Rev. 3.0, 03/31/04 BASES LCO (continued)
The MSLB (Ref. 2) and the boron dilution (Ref. 3) accidents are the most limiting analyses that establish the SDM value of the LCO. For MSLB accidents, if the LCO is violated, there is a potential to exceed the DNBR limit and to exceed 10 CFR 100, "Reactor Site Criteria," limits (Ref. 4).
For the boron dilution accident, if the LCO is violated, the minimum required time assumed for operator action to terminate dilution may no longer be applicable.
APPLICABILITY In MODE 2 with k eff < 1.0 and in MODES 3, 4, and 5, the SDM requirements are applicable to provide sufficient negative reactivity to meet the assumptions of the safety analyses discussed above. In MODE 6, the shutdown reactivity requirements are given in LCO 3.9.1, "Boron Concentration." In MODES 1 and 2, SDM is ensured by complying with LCO 3.1.5, "Shutdown Bank Insertion Limits," and LCO 3.1.6.
ACTIONS A.1 If the SDM requirements are not met, boration must be initiated promptly.
A Completion Time of 15 minutes is adequate for an operator to correctly align and start the required systems and components. It is assumed that boration will be continued until the SDM requirements are met.
In the determination of the required combination of boration flow rate and boron concentration, there is no unique requirement that must be satisfied. Since it is imperative to raise the boron concentration of the RCS as soon as possible, the boron concentration should be a highly concentrated solution, such as that normally found in the boric acid storage tank, or the borated water storage tank. The operator should borate with the best source available for the plant conditions.
In determining the boration flow rate, the time in core life must be considered. For instance, the most difficult time in core life to increase the RCS boron concentration is at the beginning of cycle when the boron concentration may approach or exceed 2000 ppm. Assuming that a value
of 1% k/k must be recovered and a boration flow rate of [ ] gpm, it is possible to increase the boron concentration of the RCS by 100 ppm in approximately 35 minutes. If a boron worth of 10 pcm/ppm is assumed, this combination of parameters will increase the SDM by 1% k/k. These boration parameters of [ ] gpm and [ ] ppm represent typical values and
are provided for the purpose of offering a specific example.
1 1 1 5 4 6 in MODE with k eff > 1.0 40 13,000 40 5 550.67 Accident Source Term refueling 1 12 1 1are the typical values when borating from the boric acid storage tank SDM B 3.1.1 WOG STS B 3.1.1-5 Rev. 3.0, 03/31/04 BASES SURVEILLANCE SR 3.1.1.1 REQUIREMENTS In MODES 1 and 2 with K eff 1.0, SDM is verified by observing that the requirements of LCO 3.1.5 and LCO 3.1.6 are met. In the event that a rod is known to be untrippable, however, SDM verification must account for the worth of the untrippable rod as well as another rod of maximum
worth. 7 In MODES 3, 4, and 5, the SDM is verified by performing a reactivity balance calculation, considering the listed reactivity effects: MODE 2 with k eff <1.0 and in a. RCS boron concentration,
- b. Control bank position, c. RCS average temperature, d. Fuel burnup based on gross thermal energy generation, e. Xenon concentration, f. Samarium concentration, and
- g. Isothermal temperature coefficient (ITC).
Using the ITC accounts for Doppler reactivity in this calculation because the reactor is subcritical, and the fuel temperature will be changing at the
same rate as the RCS.
The Frequency of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is based on the generally slow change in required boron concentration and the low probability of an accident occurring without the required SDM. This allows time for the operator to collect the required data, which includes performing a boron concentration analysis, and complete the calculation.
REFERENCES 1. 10 CFR 50, Appendix A, GDC 26.
- 2. FSAR, Chapter [15].
- 3. FSAR, Chapter [15].
- 4. 10 CFR 100.
- ; ; ; ; ; Section 14.2.5 Section 14.1.450.67 USAR, Section 3.1.2.3, GDC 27, "Redundancy of Reactivity Control." 6 2 2 2 2 2 2 8 4 82. USAR, Section 3.1.2.4, GDC 28, "Reactivity Hot Shutdown Capability
." 5 U 3. USAR, Section 3.1.2.6, GDC 30, "Reactivity Holddown Capability." 5 8 5 6 1 JUSTIFICATION FOR DEVIATIONS ITS 3.1.1 BASES, SHUTDOWN MARGIN (SDM)
- 1. Changes are made (additions, deletions, and/or changes) to the ISTS Bases which reflect the plant specific nomenclature, number, reference, system description, analysis, or licensing basis description.
- 2. The punctuation corrections have been made consistent with the Writer's Guide from the Improved Technical Specifications, TSTF-GG-05-01, Section 5.1.3.
- 3. ISTS 3.1.1 Applicable Safety Analyses states, in part, that in addition to the limiting Main Steam Line Break (MSLB), the SDM requirements must also protect against inadvertent boron dilution, an uncontrolled rod withdrawal from subcritical or low power condition, startup of an inactive reactor coolant pump (RCP), and rod ejection. For the description of the event, the ISTS Bases states that the "startup of an inactive RCP will not result in a "cold water" criticality, even if the maximum difference in temperature exists between the SG and the core. The maximum positive reactivity addition that can occur due to an inadvertent RCP start is less than half the minimum required SDM. Startup of an idle RCP cannot, therefore, produce a return to power from the hot standby condition. USAR, Section 14.1.5, the Startup of an Inactive Reactor Coolant Loop, states that if the plant were to operate with one
reactor coolant pump (RCP) out-of-service, there would be reverse flow through the inactive loop due to the pressure difference across the reactor vessel and because there are no isolation valves or check valv es in the reactor coolant loops. The cold leg temperature in the inactive loop is identical to the cold leg temperature of the active loop (the reactor core inlet temperature). Therefore, a startup of an inactive RCP would not cause a discernable power excursion, since water colder than the operating loop is not being added to the reactor vessel. Thus, the ITS 3.1.1 Bases has been modified to delete the startup of an inactive RCP requirements.
- 4. The Applicable Safety Analyses discussion states SDM satisfies Criterion 2 of 10 CFR 50.36(c)(2)(ii). It also says that even though SDM is not directly observed from the control room, SDM is considered an initial condition process variable because it is periodically monitored to ensure that the unit is operating within the bounds of the accident analysis assumptions. The additional sentence has been
deleted. The NRC Final Policy Statement on Technical Improvements of July 22, 1993 (58 FR 39132) states that process variable captured by Criterion 2 are not limited to only those directly monitored and controlled from the control room. It also states that Criterion 2 includes other features or characteristics that are specifically assumed in Design Basis Accident and Transient analyses even if they
cannot be directly observed in the cont rol room (e.g., moderator temperature coefficient and hot channel factors). Since the Final Policy Statement provides guidance on which types of parameters satisfy Criterion 2, there is no reason to
duplicate these words in the KPS ITS.
- 5. The ISTS contains bracketed information and/or values that are generic to all Westinghouse vintage plants. The brackets are removed and the proper plant specific information/value is provided. This is acceptable since the generic specific information/value is revised to reflect the current plant design.
- 6. ISTS SR 3.1.1.1 Bases states, in part, that in MODES 1 and 2 with k eff 1.0, SDM is verified by observing that the requirements of LCO 3.1.5 and LCO 3.1.6 are met. It continues by stating, in part, that in MODES 3, 4, and 5, the SDM is verified by performing a reactivity balance calculation. ITS SR 3.1.1.1 Bases states, in part, that Kewaunee Power Station Page 1 of 2 JUSTIFICATION FOR DEVIATIONS ITS 3.1.1 BASES, SHUTDOWN MARGIN (SDM)
Kewaunee Power Station Page 2 of 2 in MODES 1 and 2 with k eff 1.0, SDM is verified by observing that the requirements of LCO 3.1.5 and LCO 3.1.6 are met. It continues by stating, in part, that in MODE 2 with k eff < 1.0 and in MODES 3, 4, and 5, the SDM is verified by performing a reactivity balance calculation. This changes the ISTS by stating that in MODE 2 with
k eff < 1.0 the SDM is verified by performing a reactivity balance calculation. This is acceptable because the ISTS did not state that a reactivity balance calculation is performed when the k eff < 1.0 in MODE 2.
- 7. Typographical error corrected.
- 8. The ISTS lists GDC 26 of Appendix A to 10 CFR 50 as the reference document for the requirement that there be two independent reactivity control systems of different design principles. Per the information contained in USAR Section 1.8, Kewaunee
Power Station (KPS) was designed, constr ucted, and is being operated to comply with the Atomic Energy Commission (AEC) General Design Criteria (GDC) for Nuclear Power Plant Construction Permits, as proposed on July 10, 1967. Since the plant was approximately 50% complete prior to the February 20, 1971 issuance of 10 CFR 50 Appendix A General Design Criteria, KPS was not required to be reanalyzed and the Final Safety Analysis Report (FSAR) was not required to be revised to reflect these later criteria. However, the AEC Safety Evaluation Report (SER), issued July 24, 1972, acknowledged that the AEC staff assessed the plant, as described in the FSAR (Amendment No. 7), against the Appendix A design criteria and determined that the plant design generally conforms to the intent of the Appendix A criteria. As a result, KPS utilizes AEC GDC 27, "Redundancy of Reactivity Control," GDC 28, "Reactivity Hot Shutdown Capability," and GDC 30, "Reactivity Holddown Capability", as the licensing reference documents for the design principles.
- 9. Clarification has been added since all the reactor safety analyses are not in USAR Chapter 14.
- 10. KPS does not analyze a boron dilution event in MODE 5. As stated in KPS USAR, Section 14.1.4.2, boron dilutions during cold shutdown are not part of the KPS licensing basis.
Specific No Significant Haza rds Considerations (NSHCs)
DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATIONS ITS 3.1.1, SHUTDOWN MARGIN (SDM) There are no specific NSHC discussions for this Specification.
Kewaunee Power Station Page 1 of 1 ATTACHMENT 2 ITS 3.1.2, CORE REACTIVITY Current Technical Specification (CTS) Markup and Discussion of Changes (DOCs)
A01 ITS 3.1.2 ITS 4.9 REACTIVITY ANOMALIES APPLICABILITY Applies to potential reactivity anomalies.
OBJECTIVE To require evaluation of reactivity anomalies within the reactor.
SPECIFICATION Add proposed Applicability A02 Following a normalization of the computed boron concentration as a function of burnup, the actual boron concentration of the coolant shall be periodically compared with the predicted value. If the difference between the observed and predicted steady-state concentrations reaches the equivalent of 1% in reactivity, an evaluation as to the cause of the discrepancy
shall be made and reported to the Commission within 30 days.
M01 SR 3.1.2.1 LCO 3.1.2 M02 Add proposed ACTION A and B Amendment No. 122 TS 4.9-1 12/21/95 Page 1 of 1 DISCUSSION OF CHANGES ITS 3.1.2, CORE REACTIVITY ADMINISTRATIVE CHANGES A01 In the conversion of the Kewaunee Power Station (KPS) Current Technical Specifications (CTS) to the plant specific Improved Technical Specifications (ITS), certain changes (wording preferences, editorial changes, reformatting, revised numbering, etc.) are made to obtain consistency with NUREG-1431, Rev. 3.0, "Standard Technical Specifications-Westinghouse Plants" (ISTS).
These changes are designated as administrative changes and are acceptable because they do not result in technical changes to the CTS.
A02 CTS 4.9 requires a comparison of the actual boron concentration with the predicted (computer) value, and requires the difference between the computed boron concentration, as a function of burnup, and the actual boron concentration
to be +/- 1% k/k. ITS 3.1.2 also requires the comparison of the actual boron concentration with the predicted value and requires the difference to be within
+/- 1% k/k, but specifically states that the Applicability is in MODES 1 and 2. This changes the CTS by stating the specific MODES.
This change is acceptable because the required MODES have not changed. When full power is initially reached, the boron concentration is measured and the predicted curve is adjusted to this point. As power operation proceeds, the measured boron concentration is compared with the predicted concentration and the slope of the actual curve relating burn-up and reactivity is compared with that of the predicted curve. Therefore, since the comparison of the actual boron concentration to the predicted concentration and the computed boron concentration is a function of burnup (which can only occur when the reactor is critical) it can only be performed in MODES 1 and 2. This change is considered administrative because the technical requirements have not changed.
MORE RESTRICTIVE CHANGES M01 CTS 4.9 states, in part, that after normalization, the actual boron concentration of the coolant shall be periodically compared with the predicted value. ITS SR 3.1.2.1 requires verification of the measured core reactivity is within
+/- 1% k/k of predicted values at least once prior to entering MODE 1 after each refueling and after 60 effective full power days (EFPD) it should be verified every 31 EFPD thereafter. This changes the CTS by specifying Frequencies for verifying measured core reactivity is within +/- 1% k/k of predicted values.
This change is acceptable because it requires a verification that core reactivity is within +/- 1% k/k of predicted values thus assuring agreement between the actual core design and the core design predictions prior to entering MODE 1 after each refueling, and every 31 EFPD after 60 EFPD. This verification provides additional confidence that the core design is acceptable for operation at full power. This change is designated as more restrictive because it adds Surveillance Requirement frequencies that do not appear in the CTS.
M02 CTS 4.9 requires that if the difference between the observed and predicted steady-state concentrations reach the equivalent of 1% in reactivity, that an Kewaunee Power Station Page 1 of 3 DISCUSSION OF CHANGES ITS 3.1.2, CORE REACTIVITY evaluation as to the cause of the discrepancy shall be made and reported to the Commission within 30 days. ITS 3.1.2 requires that if the measured core reactivity is not within limits, within 7 days a re-evaluation of the core design and safety analysis, a determination that the reactor core is acceptable for continued operation, and establishment of appropriate operating restrictions and SRs are required. If the re-evaluation of the core design and safety analysis to determine that the reactor core is acceptable for continued operation, and the establishment of appropriate operating restrictions and SRs can not be accomplished within 7 days, then the reactor is required to be in MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. This changes the CTS by requiring a re-evaluation of the core design and safety analysis, a determination that the reactor core is acceptable for continued operation, and establishment of appropriate operating restrictions and SRs instead of requiring an evaluation of the cause of the discrepancy shall be made and reported to the Commission. This also changes the Completion Time from
30 days to 7 days.
This change is acceptable because the proposed Required Actions are used to establish remedial measures that must be taken in response to the degraded conditions in order to minimize risk associated with continued operation while providing an appropriate amount of time to ensure continued safe operation and re-evaluate the core design and safety analyses. The Required Actions are consistent with safe operation under the specified Condition, considering the operability status of the redundant systems of required features, the capacity and capability of remaining features, a reasonable time for repairs or replacement of required features, and the low probability of a DBA occurring during the repair period. Should the core reactivity balance requirement not be met, time is required to determine the cause of the disagreement and what, if any, adjustments are needed to the operating conditions of the core. The startup physics testing program is used to verify most of the critical core design parameters, such as control rod worth, boron worth, and moderator temperature coefficient. In addition, there is considerable conservatism in the application of these values in the accident analysis. Therefore, allowing a time to evaluate the difference and make any adjustments to the operational controls is acceptable.
The 7 day Completion time is reasonable considering the complexity of the evaluations and the time to meet administrative requirements, such as 10 CFR 50.59 safety evaluation preparation and approval. If it cannot be determined within 7 days that the core is acceptable for continued operation, the unit must be shutdown. This change is designated as more restrictive because more stringent Required Actions are being applied in the ITS than were applied in the CTS.
RELOCATED SPECIFICATIONS None
REMOVED DETAIL CHANGES None Kewaunee Power Station Page 2 of 3 DISCUSSION OF CHANGES ITS 3.1.2, CORE REACTIVITY Kewaunee Power Station Page 3 of 3 LESS RESTRICTIVE CHANGES None Improved Standard Technical Specifications (ISTS) Markup and Justification for Deviations (JFDs)
Core Reactivity 3.1.2 WOG STS 3.1.2-1 Rev. 3.0, 03/31/04 CTS 3.1 REACTIVITY CONTROL SYSTEMS
3.1.2 Core Reactivity
LCO 3.1.2 The measured core reactivity shall be within +/- 1% k/k of predicted values. 4.9 APPLICABILITY: MODES 1 and 2. DOC A02 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME
A. Measured core reactivity not within limit.
A.1 Re-evaluate core design and safety analysis, and determine that the reactor core is acceptable for continued operation.
AND A.2 Establish appropriate operating restrictions and SRs. 7 days
7 days B. Required Action and associated Completion Time not met.
B.1 Be in MODE 3.
6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> 4.9 4.9
Core Reactivity 3.1.2 WOG STS 3.1.2-2 Rev. 3.0, 03/31/04 CTS SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.1.2.1 ---------------------------NOTE----------------------------------
The predicted reactivity values may be adjusted (normalized) to correspond to the measured core reactivity prior to exceeding a fuel burnup of 60 effective full power days (EFPD) after each fuel loading. ---------------------------------------------------------------------
Verify measured core reactivity is within +/- 1% k/k of predicted values.
Once prior to
entering MODE 1
after each refueling AND
NOTE--------
Only required
after 60 EFPD ------------------------
31 EFPD thereafter
4.9 JUSTIFICATION
FOR DEVIATIONS ITS 3.1.2, CORE REACTIVITY None Kewaunee Power Station Page 1 of 1 Improved Standard Technical Specifications (ISTS) Bases Markup and Bases Justification for Deviations (JFDs)
Core Reactivity B 3.1.2 WOG B 3.1.2-1 Rev. 3.0, 03/31/04 B 3.1 REACTIVITY CONTROL SYSTEMS
B 3.1.2 Core Reactivity
BASES BACKGROUND According to GDC 26, GDC 28, and GDC 29 (Ref. 1), reactivity shall be controllable, such that subcriticality is maintained under cold conditions, and acceptable fuel design limits are not exceeded during normal operation and anticipated operational occurrences. Therefore, reactivity balance is used as a measure of the predicted versus measured core reactivity during power operation. The periodic confirmation of core reactivity is necessary to ensure that Design Basis Accident (DBA) and transient safety analyses remain valid. A large reactivity difference could be the result of unanticipated changes in fuel, control rod worth, or operation at conditions not consistent with those assumed in the predictions of core reactivity, and could potentially result in a loss of SDM or violation of acceptable fuel design limits. Comparing predicted versus measured core reactivity validates the nuclear methods used in the safety analysis and supports the SDM demonstrations (LCO 3.1.1, "SHUTDOWN MARGIN (SDM)") in ensuring the reactor can be brought safely to cold, subcritical conditions. INSERT 1 1 When the reactor core is critical or in normal power operation, a reactivity balance exists and the net reactivity is zero. A comparison of predicted and measured reactivity is convenient under such a balance, since parameters are being maintained relatively stable under steady state power conditions. The positive reactivity inherent in the core design is balanced by the negative reactivity of the control components, thermal feedback, neutron leakage, and materials in the core that absorb neutrons, such as burnable absorbers producing zero net reactivity. Excess reactivity can be inferred from the boron letdown curve (or critical boron curve), which provides an indication of the soluble boron concentration in the Reactor Coolant System (RCS) versus cycle burnup.
Periodic measurement of the RCS boron concentration for comparison with the predicted value with other variables fixed (such as rod height, temperature, pressure, and power), provides a convenient method of ensuring that core reactivity is within design expectations and that the calculational models used to generate the safety analysis are adequate.
In order to achieve the required fuel cycle energy output, the uranium enrichment, in the new fuel loading and in the fuel remaining from the previous cycle, provides excess posit ive reactivity beyond that required to sustain steady state operation throughout the cycle. When the reactor is (which includes reactor safety analyses not in USAR Chapter 14) 6 B 3.1.2 1 INSERT 1 Two independent reactivity control systems, preferably from different principles, shall be provided (Ref. 1). The reactivity control systems provided shall be capable of making and holding the core sub-critical from any hot standby or hot operation condition (Ref. 2). One of the reactivity control systems provided shall be capable of making the core sub-critical under any anticipated operating condition (including anticipated operational tr ansients) sufficiently fast to prevent exceeding acceptable fuel damage limits. Shutdown margin should assure sub-criticality with the most reactive control rod fully withdrawn (Ref. 3). The reactivity control system provided shall be capable of making the core sub-critical under credible accident conditions with appropriate margins for contingencies and limiting any subsequent return to power such that there will be no undue risk to the health and safety of the public (Ref. 4).
Insert Page B 3.1.2-1 Core Reactivity B 3.1.2 WOG B 3.1.2-2 Rev. 3.0, 03/31/04 BASES BACKGROUND (continued)
critical at RTP and moderator temperature, the excess positive reactivity is compensated by burnable absorbers (if any), control rods, whatever neutron poisons (mainly xenon and samarium) are present in the fuel, and the RCS boron concentration.
When the core is producing THERMAL POWER, the fuel is being depleted and excess reactivity is decreasing. As the fuel depletes, the RCS boron concentration is reduced to decrease negative reactivity and maintain constant THERMAL POWER. The boron letdown curve is based on steady state operation at RTP. Therefore, deviations from the predicted boron letdown curve may indicate deficiencies in the design analysis, deficiencies in the calculational models, or abnormal core conditions, and must be evaluated.
APPLICABLE The acceptance criteria for core reactivity are that the reactivity balance SAFETY limit ensures plant operation is maintained within the assumptions of ANALYSES the safety analyses.
Accurate prediction of core reactivity is either an explicit or implicit assumption in the accident analysis evaluations. Every accident evaluation (Ref. 2) is, therefore, dependent upon accurate evaluation of core reactivity. In particular, SDM and reactivity transients, such as control rod withdrawal accidents or rod ejection accidents, are very sensitive to accurate prediction of core reactivity. These accident analysis evaluations rely on computer codes that have been qualified against available test data, operating plant data, and analytical benchmarks. Monitoring reactivity balance additionally ensures that the nuclear methods provide an accurate representation of the core reactivity.
5 1 Design calculations and safety analyses are performed for each fuel cycle for the purpose of predetermining reactivity behavior and the RCS boron concentration requirements for reactivity control during fuel depletion.
The comparison between measured and predicted initial core reactivity provides a normalization for the calculational models used to predict core reactivity. If the measured and predicted RCS boron concentrations for identical core conditions at beginning of cycle (BOC) do not agree, then the assumptions used in the reload cycle design analysis or the calculational models used to predict soluble boron requirements may not be accurate. If reasonable agreement between measured and predicted core reactivity exists at BOC, then the prediction may be normalized to Core Reactivity B 3.1.2 WOG B 3.1.2-3 Rev. 3.0, 03/31/04 BASES APPLICABLE SAFETY ANALYSES (continued)
the measured boron concentration. Thereafter, any significant deviations in the measured boron concentration from the predicted boron letdown curve that develop during fuel depletion may be an indication that the calculational model is not adequate for core burnups beyond BOC, or that an unexpected change in core conditions has occurred.
The normalization of predicted RCS boron concentration to the measured value is typically performed after reaching RTP following startup from a refueling outage, with the control rods in their normal positions for power operation. The normalization is performed at BOC conditions, so that
core reactivity relative to predicted values can be continually monitored and evaluated as core conditions change during the cycle.
Core reactivity satisfies Criterion 2 of 10 CFR 50.36(c)(2)(ii).
LCO Long term core reactivity behavior is a result of the core physics design and cannot be easily controlled once the core design is fixed. During operation, therefore, the LCO can only be ensured through measurement and tracking, and appropriate actions taken as necessary. Large differences between actual and predicted core reactivity may indicate that the assumptions of the DBA and transient analyses are no longer valid, or that the uncertainties in the Nuclear Design Methodology are larger than expected. A limit on the reactivity balance of +/- 1% k/k has been established based on engineering judgment. A 1% deviation in reactivity from that predicted is larger than expected for normal operation and should therefore be evaluated.
When measured core reactivity is within 1% k/k of the predicted value at steady state thermal conditions, the core is considered to be operating within acceptable design limits. Si nce deviations from the limit are normally detected by comparing predicted and measured steady state RCS critical boron concentrations, the difference between measured and predicted values would be approximately 100 ppm (depending on the boron worth) before the limit is reached. These values are well within the uncertainty limits for analysis of boron concentration samples, so that spurious violations of the limit due to uncertainty in measuring the RCS boron concentration are unlikely.
140 3 3much larger than APPLICABILITY The limits on core reactivity must be maintained during MODES 1 and 2 because a reactivity balance must exist when the reactor is critical or producing THERMAL POWER. As the fuel depletes, core conditions are changing, and confirmation of the reactivity balance ensures the core is operating as designed. This Specification does not apply in MODES 3, 4, and 5 because the reactor is shut down and the reactivity balance is not changing.
Core Reactivity B 3.1.2 WOG B 3.1.2-4 Rev. 3.0, 03/31/04 BASES APPLICABILITY (continued)
In MODE 6, fuel loading results in a continually changing core reactivity. Boron concentration requirements (LCO 3.9.1, "Boron Concentration") ensure that fuel movements are performed within the bounds of the safety analysis. An SDM demonstration is required during the first startup following operations that could have altered core reactivity (e.g., fuel movement, control rod replacement, control rod shuffling).
ACTIONS A.1 and A.2
Should an anomaly develop between measured and predicted core reactivity, an evaluation of the core design and safety analysis must be performed. Core conditions are evaluated to determine their consistency with input to design calculations. Measured core and process parameters are evaluated to determine that they are within the bounds of the safety analysis, and safety analysis calculational models are reviewed to verify that they are adequate for representation of the core conditions. The required Completion Time of 7 days is based on the low probability of a DBA occurring during this period, and allows sufficient time to assess the physical condition of the reactor and complete the evaluation of the core design and safety analysis.
Following evaluations of the core design and safety analysis, the cause of the reactivity anomaly may be resolved. If the cause of the reactivity anomaly is a mismatch in core conditions at the time of RCS boron concentration sampling, then a recalculation of the RCS boron concentration requirements may be performed to demonstrate that core
reactivity is behaving as expected. If an unexpected physical change in the condition of the core has occurred, it must be evaluated and corrected, if possible. If the cause of the reactivity anomaly is in the calculation technique, then the calculational models must be revised to provide more accurate predictions. If any of these results are demonstrated, and it is concluded that the reactor core is acceptable for continued operation, then the boron letdown curve may be renormalized and power operation may continue. If operational restriction or additional SRs are necessary to ensure the reactor core is acceptable for continued operation, then they must be defined.
The required Completion Time of 7 days is adequate for preparing whatever operating restrictions or Surveillances that may be required to allow continued reactor operation.
Core Reactivity B 3.1.2 WOG B 3.1.2-5 Rev. 3.0, 03/31/04 BASES ACTIONS (continued)
B.1 If the core reactivity cannot be restored to within the 1% k/k limit, the plant must be brought to a MODE in which the LCO does not apply. To achieve this status, the plant must be brought to at least MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. If the SDM for MODE 3 is not met, then the boration required by SR 3.1.1.1 would occur. The allowed Completion Time is reasonable, based on operating experience, for reaching MODE 3 from full power conditions in an orderly manner and without challenging plant systems. If any Required Action and associated Completion Time is not met 1 2 4 3 5 SURVEILLANCE SR 3.1.2.1 REQUIREMENTS Core reactivity is verified by periodic comparisons of measured and predicted RCS boron concentrations. The comparison is made, considering that other core conditions are fixed or stable, including control rod position, moderator temperature, fuel temperature, fuel depletion, xenon concentration, and samarium concentration. The Surveillance is performed prior to entering MODE 1 as an initial check on core conditions and design calculations at BOC. The SR is modified by a Note. The Note indicates that the normalization of predicted core reactivity to the measured value must take place within the first 60 effective full power days (EFPD) after each fuel loading. This allows sufficient time for core conditions to reach steady state, but prevents operation for a large fraction of the fuel cycle without establishing a benchmark for the design calculations. The required subsequent Frequency of 31 EFPD, following the initial 60 EFPD after entering MODE 1, is acceptable, based on the slow rate of core changes due to fuel depletion and the presence of other indicators (QPTR, AFD, etc.) for prompt indication of an anomaly.
may REFERENCES 1. 10 CFR 50, Appendix A, GDC 26, GDC 28, and GDC 29.
- 2. FSAR, Chapter [15].
USAR, Section 3.1.2.3, GDC 27, "Redundancy of Reactivity Control." 14 U 5 2. USAR, Section 3.1.2.4, GDC 28, "Reactivity Hot Shutdown Capability." 3. USAR, Section 3.1.2.5, GDC 29, "Reactivity Shutdown Capability." 4. USAR, Section 3.1.2.6, GDC 30, "Reactivity Holddown Capability."
JUSTIFICATION FOR DEVIATIONS ITS 3.1.2 BASES, CORE REACTIVITY
- 1. ISTS 3.1.2 Bases Background references General Design Criteria. Kewaunee Power Station (KPS) was designed prior to promulgation of 10 CFR 50, Appendix A. Therefore, ITS 3.1.2 Bases Background has been revised to discuss the design standards used by KPS. Additionally, bases references to 10 CFR 50, Appendix A have been replaced with references to the appropriate section of the USAR.
Subsequent reference numbers have been renumbered.
- 2. ITS 3.1.2 ACTION B requires that when the Required Action and associated Completion Time of Condition A is not met, to be in MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. ISTS
3.1.2 Bases
statement for ACTION B.1 which states "if the core reactivity cannot be restored to within the 1% k/k limit-" has been changed to match the wording contained in Condition B. Furthermore, ACTION A contains two Required Actions, and the "restore" words in the ISTS Bases are not consistent with either of the Required Actions. Therefore, changes have been made to be consistent with the Specification.
- 3. Changes are made (additions, deletions, and/or changes) to the ISTS Bases which reflect the plant specific nomenclature, number, reference, system description, analysis, or licensing basis description.
- 4. The ISTS contains bracketed information and/or values that are generic to all Westinghouse vintage plants. The brackets are removed and the proper plant specific information/value is provided. This is acceptable since the generic specific information/value is revised to reflect the current plant design.
- 5. Change made to be consistent with the actual wording of the Note in ISTS SR 3.1.2.1. Also the proposed wording (use of "may") is consistent with a similar description concerning normalization in the Applicable Safety Analyses section of the Bases.
- 6. Clarification has been added since all the reactor safety analyses are not in USAR Chapter 14.
Kewaunee Power Station Page 1 of 1 Specific No Significant Haza rds Considerations (NSHCs)
DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATIONS ITS 3.1.2, CORE REACTIVITY There are no specific NSHC discussions for this Specification.
Kewaunee Power Station Page 1 of 1 ATTACHMENT 3 ITS 3.1.3, MODERATOR TEMP ERATURE COEFFICIENT (MTC)
Current Technical Specification (CTS) Markup and Discussion of Changes (DOCs)
A01 ITS 3.1.3ITS f. Minimum Conditions for Criticality
- 1. The reactor shall not be brought to a critical condition until the pressure-temperature state is to the right of the criticality limit line shown in Figure TS 3.1-1.
- 2. The reactor shall be maintained subcritical by at least 1% k/k until normal water level is established in the pressurizer.
- 3. When the reactor is critical the moderator temperature coefficient shall be as specified in the COLR, except during LOW POWER PHYSICS TESTING. The maximum upper moderator temperature coefficient limit shall be 5 pcm/ F for power levels 60% RATED POWER and 0 pcm/ F for power levels 60% RATED POWER. LCO 3.1.3 See ITS 3.1.8 M01 A pplicabilit y See ITS 3.4.9 See ITS 3.4.3 4. If the limits of 3.1.f.3 cannot be met, then power operation may continue provided the following actions are taken:
A. Within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, develop and maintain administrative control rod withdrawal limits sufficient to restore the moderator temperature coefficient to within the limits specified in TS 3.1.f.3. These withdrawal limits shall be in addition to the
insertion limits specified in TS 3.10.d.
B. If the actions specified in TS 3.1.f.4.A are not satisfied, then be in HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
LA01M02 A CTION A A CTION B M01Add proposed ACTION C M03Add proposed SR 3.1.3.1 and SR 3.1.3.2 Amendment No. 165 TS 3.1-10 03/11/2003 Page 1 of 1 DISCUSSION OF CHANGES ITS 3.1.3, MODERATOR TEMPERATURE COEFFICIENT (MTC)
ADMINISTRATIVE CHANGES A01 In the conversion of the Kewaunee Power Station (KPS) Current Technical Specifications (CTS) to the plant specific Improved Technical Specifications (ITS), certain changes (wording preferences, editorial changes, reformatting, revised numbering, etc.) are made to obtain consistency with NUREG-1431, Rev. 3.0, "Standard Technical Specifications-Westinghouse Plants" (ISTS).
These changes are designated as administrative changes and are acceptable because they do not result in technical changes to the CTS.
MORE RESTRICTIVE CHANGES
M01 CTS 3.1.f.3 requires, in part, that the moderator temperature coefficient (MTC) shall be as specified in the COLR when the reactor is critical. The COLR provides both an upper MTC limit and a lower MTC limit. If an MTC limit is not met, CTS 3.1.f.4 provides 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to develop and maintain administrative control rod withdrawal limits sufficient to restore the MTC to within the limits.
ITS 3.1.3 requires the upper MTC Limit to be met in MODE 1 and MODE 2 with
k eff 1.0 and the lower MTC limit to be met in MODES 1, 2, and 3. Furthermore, ITS 3.1.3 does not provide any time to restore the lower MTC to within limits. If the lower MTC limit is not met, ITS 3.1.3 ACTION C requires the unit to be in MODE 4 within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, which places the unit outside the new proposed Applicability. This changes the CTS by requiring the lower MTC limit to be met in MODE 3 and when it cannot be met, to be in MODE 4 within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
This change is acceptable because the lower MTC limit is required in MODE 3, in addition to MODE 2, to ensure that core overcooling accidents will not violate the assumptions in the safety analyses. This change is designated as more restrictive because it expands the Applicability for the lower MTC limit and requires an immediate shutdown to MODE 4 in lieu of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to restore MTC to within its lower limit prior to requiring a unit shutdown.
M02 CTS 3.10.f.4.B requires that if the development and maintenance of administrative control rod withdrawal limits sufficient to restore the moderator temperature coefficient to within the limits specified in the COLR can not be satisfied within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, then to be in HOT STANDBY within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. The reactivity condition (k/k) for HOT STANDBY, as defined in CTS 1.0.j, is < 0.25%. Under similar conditions (i.e., if the establishment of administrative withdrawal limits for control banks to maintain MTC within limit is not met within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />) ITS 3.1.3 ACTION B requires the unit to be in MODE 2 with k eff < 1.0 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. This changes the CTS by requiring the unit to be in MODE 2 with
k eff < 1.0 (i.e., k/k < 0.0%) in lieu of k/k < 0.25%.
The purpose of CTS 3.10.f.4.B is to place the unit in a condition in which it does not rely on the MTC upper limit. In ITS 3.1.3, it is necessary to place the unit in MODE 2 with k eff < 1.0. At this point, the unit will be outside of the MODE of Applicability for upper MTC limit (MODE 1 and MODE 2 with k eff 1.0). This change is designated as more restrictive because the ITS requires the unit to be Kewaunee Power Station Page 1 of 3 DISCUSSION OF CHANGES ITS 3.1.3, MODERATOR TEMPERATURE COEFFICIENT (MTC) made subcritical (i.e., MODE 2 with k eff < 1.0, which is the same as k/k < 0.0%) in lieu of the CTS requirement to just be in HOT STANDBY (k/k < 0.25%).
M03 CTS 3.1.f.3 does not provide any Surveillance Requirements for verifying that the MTC is within the limits specified in the COLR. ITS SR 3.1.3.1 requires verification that the MTC is within the upper limit prior to entering MODE 1 after each refueling. ITS SR 3.1.3.2 requires that the MTC is within the lower limit once each cycle. This changes the CTS by adding new Surveillance Requirements to verify the upper and lower MTC are within limits.
This change is acceptable because the added Surveillance Requirements verify that the MTC requirements will be met in MODE 1 and MODE 2 with k eff 1.0 for the upper limit and MODES 1, 2, and 3 for the lower limit. This change is designated as more restrictive because new Surveillance Requirements are being added to the ITS that are not included in the CTS.
RELOCATED SPECIFICATIONS
None REMOVED DETAIL CHANGES
LA01 (Type 3 - Removing Procedural Details for Meeting TS Requirements or Reporting Requirements) CTS 3.10.f.4.A requires, in part, the development and maintenance of administrative control rod withdrawal limits sufficient to restore the moderator temperature coefficient to within the limits specified in the COLR.
Additionally, CTS 3.10.f.4.A states that the withdrawal limits shall be in addition to the insertion limits specified in rod insertion limits. ITS 3.1.3 Required Action A.1 requires the establishment of withdrawal limits for control banks to maintain MTC within limits. This changes the CTS by moving the statement that these withdrawal limits shall be in addition to the insertion limits specified in rod
insertion limits to the Bases.
The removal of these details for meeting the Required Action from the Technical Specification is acceptable because this type of information is not necessary to be included in the Technical Specifications to provide adequate protection of public health and safety. The ITS still retains the requirement to establish withdrawal limits for control banks to maintain MTC within limits. Also, this change is acceptable because these type of procedural details will be adequately controlled in the ITS Bases. Changes to the Bases are controlled by the Technical Specification Bases Control Program in Chapter 5. This change is designated as less restrictive removal of detail change because procedural details for meeting Technical Specification requirements are being removed from the Technical Specifications.
Kewaunee Power Station Page 2 of 3 DISCUSSION OF CHANGES ITS 3.1.3, MODERATOR TEMPERATURE COEFFICIENT (MTC)
Kewaunee Power Station Page 3 of 3 LESS RESTRICTIVE CHANGES None Improved Standard Technical Specifications (ISTS) Markup and Justification for Deviations (JFDs)
MTC 3.1.3 WOG STS 3.1.3-1 Rev. 3.0, 03/31/04 CTS 3.1 REACTIVITY CONTROL SYSTEMS
3.1.3 Moderator
Temperature Coefficient (MTC)
LCO 3.1.3 The MTC shall be maintained within the limits specified in the COLR. The maximum upper limit shall be [ [ ] k/k°F at hot zero power] [that specified in Figure 3.1.3-1].
5 pcm/ºF with THERMAL POWER 60% RTP and 0 pcm/ºF with THERMAL POWER > 60% RTP 3.1.f.3 1 APPLICABILITY: MODE 1 and MODE 2 with k eff 1.0 for the upper MTC limit, 3.1.f.3 MODES 1, 2, and 3 for the lower MTC limit.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. MTC not within upper limit.
A.1 Establish administrative withdrawal limits for control
banks to maintain MTC within limit.
24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> B. Required Action and associated Completion
Time of Condition A not met.
B.1 Be in MODE 2 with k eff < 1.0.
6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> C. MTC not within lower limit.
C.1 Be in MODE 4.
12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> 3.1.f.4, 3.1.f.4.A 3.1.f.4.b DOC M01 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY
SR 3.1.3.1 Verify MTC is within upper limit.
Prior to entering MODE 1 after each refueling
DOC M03 MTC 3.1.3 WOG STS 3.1.3-2 Rev. 3.0, 03/31/04 CTS SURVEILLANCE REQUIREMENTS (continued)
SURVEILLANCE FREQUENCY SR 3.1.3.2 ---------------------------NOTES--------------------------------
- 1. Not required to be performed until 7 effective full power days (EFPD) after reaching the equivalent of an equilibrium RTP all rods out (ARO) boron concentration of 300 ppm.
- 2. If the MTC is more negative than the 300 ppm Surveillance limit (not LCO limit) specified in the COLR, SR 3.1.3.2 shall be repeated once per 14 EFPD during the remainder of the fuel cycle.
- 3. SR 3.1.3.2 need not be repeated if the MTC measured at the equivalent of equilibrium RTP-ARO boron concentration of 60 ppm is less negative than the 60 ppm Surveillance limit specified in the COLR. ---------------------------------------------------------------------
Verify MTC is within lower limit.
Once each cycle DOC M03 MTC 3.1.3 WOG STS 3.1.3-3 Rev. 3.0, 03/31/04
Figure 3.1.3 - 1 (page 1 of 1) Moderator Temperature Coefficient Vs. Rated Thermal Power 1 Z W o LL LL W o o w a: ::::> << a: w 0... :::2: w I-a: o << a: w o o :::2: __ __ __ __ __ -+ __ -4 ___ UNACCf PTABLE __ .8 OPERATION
- 7 1-------+----11-------+-----+-----+-----+-------+-\
+-----+
_
- 6 i-----------+--
--Il----------+
+------+--------+------+-
_4______++_
\ ACCEPTABLE OPERATION
- 4 f-----+----++-----+--f-----+------+-----+-
+-I--4-I\---+-_
\
- 3 70 80 90 100 .2 _TH!S F! FOR !LLUSTRAT!ON ONL __
DO NOT USE FOR OPERATION
\
- 1 !-----------+--
t-----+---t-----+---
t-------+---+--
t-----------+--\
o 0 10 20 30 40 50 60 PERCENT RTP o JUSTIFICATION FOR DEVIATIONS ITS 3.1.3, MODERATOR TEMPERATURE COEFFICIENT (MTC)
- 1. The ISTS contains bracketed information and/or values that are generic to all Westinghouse vintage plants. The brackets are removed and the proper plant specific information/value is provided. This is acceptable since the generic specific information/value is revised to reflect the current plant design.
Additionally, since ISTS Figure 3.1.3-1 is a bracketed value in ISTS LCO 3.1.3 and it is not being used, ISTS Figure 3.1.3-1 is deleted.
Kewaunee Power Station Page 1 of 1 Improved Standard Technical Specifications (ISTS) Bases Markup and Bases Justification for Deviations (JFDs)
MTC B 3.1.3 WOG STS B 3.1.3-1 Rev. 3.0, 03/31/04 B 3.1 REACTIVITY CONTROL SYSTEMS
B 3.1.3 Moderator Temperature Coefficient (MTC)
BASES BACKGROUND According to GDC 11 (Ref. 1), the reactor core and its interaction with the Reactor Coolant System (RCS) must be designed for inherently stable power operation, even in the possible event of an accident. In particular, the net reactivity feedback in the system must compensate for any unintended reactivity increases. INSERT 1 1 The MTC relates a change in core reactivity to a change in reactor coolant temperature (a positive MTC means that reactivity increases with increasing moderator temperature; conversely, a negative MTC means that reactivity decreases with increasing moderator temperature). The reactor is designed to operate with a negative MTC over the largest possible range of fuel cycle operation. Therefore, a coolant temperature increase will cause a reactivity decrease, so that the coolant temperature tends to return toward its initial value. Reactivity increases that cause a coolant temperature increase will thus be self limiting, and stable power operation will result.
MTC values are predicted at selected burnups during the safety evaluation analysis and are confirmed to be acceptable by measurements. Both initial and reload cores are designed so that the beginning of cycle (BOC) MTC is less than zero when THERMAL POWER is at RTP. The actual value of the MTC is dependent on core characteristics, such as fuel loading and reactor coolant soluble boron concentration. The core design may require additional fixed distributed poisons to yield an MTC at BOC within the range analyzed in the plant accident analysis. The end of cycle (EOC) MTC is also limited by the requirements of the accident analysis. Fuel cycles that are designed to achieve high burnups or that have changes to other characteristics are evaluated to ensure that the MTC does not exceed the EOC limit.
The 2 2 The limitations on MTC are provided to ensure that the value of this coefficient remains within the limiting conditions assumed in the FSAR accident and transient analyses.
2 U B 3.1.3 1 INSERT 1 The design of the reactor core with its related controls and protection systems shall ensure that power oscillations, the magnitude of which could cause damage in excess of acceptable fuel damage limits, are not possible or can be readily suppressed (Ref. 1).
Insert Page B 3.1.3-1 o -
MTC B 3.1.3 WOG STS B 3.1.3-2 Rev. 3.0, 03/31/04 BASES BACKGROUND (continued)
If the LCO limits are not met, the unit response during transients may not be as predicted. The core could violate criteria that prohibit a return to criticality, or the departure from nucleate boiling ratio criteria of the approved correlation may be violated, which could lead to a loss of the fuel cladding integrity.
The SRs for measurement of the MTC at the beginning and near the end of the fuel cycle are adequate to confirm that the MTC remains within its limits, since this coefficient changes slowly, due principally to the reduction in RCS boron concentration associated with fuel burnup.
APPLICABLE The acceptance criteria for the specified MTC are:
SAFETY ANALYSES a. The MTC values must remain within the bounds of those used in the accident analysis (Ref. 2) and
- b. The MTC must be such that inherently stable power operations result during normal operation and accidents, such as overheating and
overcooling events.
- 3 The FSAR, Chapter 15 (Ref. 2), contains analyses of accidents that result in both overheating and overcooling of the reactor core. MTC is one of the controlling parameters for core reactivity in these accidents. Both the most positive value and most negative value of the MTC are important to safety, and both values must be bounded. Values used in the analyses consider worst case conditions to ensure that the accident results are
bounding (Ref. 3).
14 U 2 The consequences of accidents that cause core overheating must be evaluated when the MTC is positive. Such accidents include the rod withdrawal transient from either zero (Ref. 4) or RTP, loss of main feedwater flow, and loss of forced reactor coolant flow. The consequences of accidents that cause core overcooling must be evaluated when the MTC is negative. Such accidents include sudden feedwater flow increase and sudden decrease in feedwater temperature.
2 normal MTC B 3.1.3 WOG STS B 3.1.3-3 Rev. 3.0, 03/31/04 BASES APPLICABLE SAFETY ANALYSES (continued)
In order to ensure a bounding accident analysis, the MTC is assumed to be its most limiting value for the analysis conditions appropriate to each accident. The bounding value is determined by considering rodded and unrodded conditions, whether the reactor is at full or zero power, and whether it is the BOC or EOC life. The most conservative combination appropriate to the accident is then used for the analysis (Ref. 2).
MTC values are bounded in reload safety evaluations assuming steady state conditions at BOC and EOC. An EOC measurement is conducted at conditions when the RCS boron concentration reaches approximately 300 ppm. The measured value may be extrapolated to project the EOC value, in order to confirm reload design predictions.
4MTC satisfies Criterion 2 of 10 CFR 50.36(c)(2)(ii). Even though it is not directly observed and controlled from the control room, MTC is considered an initial condition process variable because of its dependence on boron concentration.
LCO LCO 3.1.3 requires the MTC to be within specified limits of the COLR to ensure that the core operates within the assumptions of the accident analysis. During the reload core safety evaluation, the MTC is analyzed to determine that its values remain within the bounds of the original accident analysis during operation.
Assumptions made in safety analyses require that the MTC be less positive than a given upper bound and more positive than a given lower bound. The MTC is most positive at BOC; this upper bound must not be exceeded. This maximum upper limit occurs at BOC, all rods out (ARO), hot zero power conditions. At EOC the MTC takes on its most negative value, when the lower bound becomes important. This LCO exists to ensure that both the upper and lower bounds are not exceeded.
2near During operation, therefore, the conditions of the LCO can only be ensured through measurement. The Surveillance checks at BOC and EOC on MTC provide confirmation that the MTC is behaving as anticipated so that the acceptance criteria are met.
are additionallyCore models provide predicted values of MTC that validate the upper and lower MTC limits in the reload safety evaluation process for each core reload. The 2
MTC B 3.1.3 WOG STS B 3.1.3-4 Rev. 3.0, 03/31/04 BASES LCO (continued)
The LCO establishes a maximum positive value that cannot be exceeded. The BOC positive limit and the EOC negative limit are established in the COLR to allow specifying limits for each particular cycle. This permits the unit to take advantage of improved fuel management and changes in unit operating schedule. (lower) (upper) 5 APPLICABILITY Technical Specifications place both LCO and SR values on MTC, based on the safety analysis assumptions described above.
In MODE 1, the limits on MTC must be maintained to ensure that any accident initiated from THERMAL POWER operation will not violate the design assumptions of the accident analysis. In MODE 2 with the reactor critical, the upper limit must also be maintained to ensure that startup and subcritical accidents (such as the uncontrolled control rod assembly or group withdrawal) will not violate the assumptions of the accident analysis. The lower MTC limit must be maintained in MODES 2 and 3, in addition to MODE 1, to ensure that cooldown accidents will not violate the assumptions of the accident analysis. In MODES 4, 5, and 6, this LCO is not applicable, since no Design Basis Accidents using the MTC as an analysis assumption are initiated from these MODES.
ACTIONS A.1 If the BOC MTC limit is violated, administrative withdrawal limits for control banks must be established to maintain the MTC within its limits.
The MTC becomes more negative with control bank insertion and decreased boron concentration. A Completion Time of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> provides enough time for evaluating the MTC measurement and computing the required bank withdrawal limits. These withdrawal limits shall be in addition to the insertion limits specified in LCO 3.1.6, "Control Bank Insertion Limits." upper 6 5 As cycle burnup is increased, the RCS boron concentration will be reduced. The reduced boron concentration causes the MTC to become more negative. Using physics calculations, the time in cycle life at which the calculated MTC will meet the LCO requirement can be determined. At this point in core life Condition A no longer exists. The unit is no longer
in the Required Action, so the administrative withdrawal limits are no longer in effect.
MTC B 3.1.3 WOG STS B 3.1.3-5 Rev. 3.0, 03/31/04 BASES ACTIONS (continued)
B.1 If the required administrative withdrawal limits at BOC are not established within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, the unit must be brought to MODE 2 with k eff < 1.0 to prevent operation with an MTC that is more positive than that assumed in safety analyses.
The allowed Completion Time of 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> is reasonable, based on operating experience, for reaching the required MODE from full power conditions in an orderly manner and without challenging plant systems.
C.1 Exceeding the EOC MTC limit means that the safety analysis assumptions for the EOC accidents that use a bounding negative MTC value may be invalid. If the EOC MTC limit is exceeded, the plant must be brought to a MODE or condition in which the LCO requirements are not applicable. To achieve this status, the unit must be brought to at least MODE 4 within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. lower lower 5 5 The allowed Completion Time is reasonable, based on operating experience, for reaching the required MODE from full power conditions in an orderly manner and without challenging plant systems.
SURVEILLANCE SR 3.1.3.1 REQUIREMENTS This SR requires measurement of the MTC at BOC prior to entering MODE 1 in order to demonstrate compliance with the most positive MTC LCO. Meeting the limit prior to entering MODE 1 ensures that the limit will also be met at higher power levels.
The BOC MTC value for ARO will be inferred from isothermal temperature coefficient measurements obtained during the physics tests after refueling. The ARO value can be directly compared to the BOC MTC limit of the LCO. If required, measurement results and predicted design values can be used to establish administrative withdrawal limits for
control banks. upper 5 2 MTC B 3.1.3 WOG B 3.1.3-6 Rev. 3.0, 03/31/04 BASES SURVEILLANCE REQUIREMENTS (continued)
In similar fashion, the LCO demands that the MTC be less negative than the specified value for EOC full power conditions. This measurement may be performed at any THERMAL POWER, but its results must be extrapolated to the conditions of RTP and all banks withdrawn in order to make a proper comparison with the LCO value. Because the RTP MTC value will gradually become more negative with further core depletion and boron concentration reduction, a 300 ppm SR value of MTC should necessarily be less negative than the EOC LCO limit. The 300 ppm SR value is sufficiently less negative than the EOC LCO limit value to ensure that the LCO limit will be met when the 300 ppm Surveillance criterion is met.
SR 3.1.3.2 is modified by three Notes that include the following
requirements:
- a. The SR is not required to be performed until 7 effective full power days (EFPDs) after reaching the equivalent of an equilibrium RTP all rods out (ARO) boron concentration of 300 ppm.
- b. If the 300 ppm Surveillance limit is exceeded, it is possible that the EOC limit on MTC could be reached before the planned EOC.
Because the MTC changes slowly with core depletion, the Frequency of 14 effective full power days is sufficient to avoid exceeding the
EOC limit.
- c. The Surveillance limit for RTP boron concentration of 60 ppm is conservative. If the measured MTC at 60 ppm is more positive than
the 60 ppm Surveillance limit, t he EOC limit will not be exceeded because of the gradual manner in which MTC changes with core
burnup. REFERENCES 1. 10 CFR 50, Appendix A, GDC 11.
3 USAR, Section 3.1.2.2, GDC 7, "Suppression of Power Oscillations." 2. FSAR, Chapter [15].
U
- 3. WCAP 9273-NP-A, "Westinghouse Reload Safety Evaluation Methodology," July 1985.
- 4. FSAR, Chapter [15].
14 3 7 9272-P-A 3 U Section 14.1.1 3 7 JUSTIFICATION FOR DEVIATIONS ITS 3.1.3 BASES, MODERATOR TEMPERATURE COEFFICIENT (MTC)
- 1. ISTS 3.1.3 Bases Background references General Design Criteria. Kewaunee Power Station (KPS) was designed prior to promulgation of 10 CFR 50, Appendix A. Therefore, ITS 3.1.3 Bases Background has been revised to discuss the design standards used by KPS. Additionally, bases references to 10 CFR 50, Appendix A have been replaced with references to the appropriate section of the USAR.
- 2. Changes are made (additions, deletions, and/or changes) to the ISTS Bases which reflect the plant specific nomenclature, number, reference, system description, analysis, or licensing basis description.
- 3. The punctuation corrections have been made consistent with the Writer's Guide from the Improved Technical Specifications, TSTF-GG-05-01, Section 5.1.3.
- 4. The Applicable Safety Analyses discussion states that MTC satisfies Criterion 2 of 10 CFR 50.36(c)(2)(ii). It also says that even though MTC is not directly observed and controlled from the control room, MTC is still considered an initial condition process variable because of its dependence on boron concentration. The additional sentence has been deleted. The NRC Final Policy Statement on Technical Improvements of July 22, 1993 (58 FR 39132) states that process variables captured
by Criterion 2 are not limited to only those directly monitored and controlled from the control room. It also states that Criterion 2 includes other features or characteristics that are specifically assumed in Design Basis Accident and Transient analyses even if they cannot be directly observed in the control room (e.g., moderator temperature coefficient and hot channel factors). Since the Final Policy Statement provides guidance on which types of parameters satisfy Criterion 2, there is no reason to
duplicate these words in the KPS CTS.
- 5. The ISTS Bases variously refer to the "upper MTC limit," the "BOC MTC limit," the "lower MTC limit," and the "EOC MTC limit." References to the BOC and EOC MTC limit are eliminated and "upper" and "lower" are substituted to eliminate confusion and to be consistent with the Specification.
- 6. This requirement has been added to the Bases consistent with the requirement in CTS 3.10.f.4.A. This clarifies the ITS 3.1.3 Required Action A.1 requirement to ensure the administrative withdrawal limits are in addition to the normal limits required by LCO 3.1.6, "Control Bank Insertion Limits."
- 7. The ISTS contains bracketed information and/or values that are generic to all Westinghouse vintage plants. The brackets are removed and the proper plant specific information/value is provided. This is acceptable since the generic specific information/value is revised to reflect the current plant design.
Kewaunee Power Station Page 1 of 1 Specific No Significant Haza rds Considerations (NSHCs)
DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATIONS ITS 3.1.3, MODERATOR TEMPERATURE COEFFICIENT (MTC) There are no specific NSHC discussions for this Specification.
Kewaunee Power Station Page 1 of 1 ATTACHMENT 4 ITS 3.1.4, ROD GROUP ALIGNMENT LIMITS Current Technical Specification (CTS) Markup and Discussion of Changes (DOCs)
ITS 3.1.4A01ITS e. Rod Misalignment Limitations NOTE: Individual RPIs may be outside their limits for
< 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> following substantial rod movement LCO 3.1.4 Note This specification defines allowable limits for misaligned rod cluster control assemblies. In TS 3.10.e.1 and TS 3.10.e.2, the magnitude, in steps, of an indicated rod misalignment may be determined by comparison of the respective bank demand step counter to the analog individual rod position indicator, the rod position as noted on the plant process computer, or through the conditioning module output voltage via a correlation of rod position vs. voltage.
Rod misalignment limitations do not apply during physics testing.
LA01See ITS 3.1.8 1. When reactor power is 85% of rating, the rod cluster control assembly shall be maintained within +/- 12 steps from their respective banks. If a rod cluster control assembly is misaligned from its bank by more than +/- 12 steps when reactor power is 85%, then the rod will be realigned or the core power peaking factors shall be determined within four hours, and TS 3.10.b applied. If peaking factors are not determined within four hours, the reactor power shall be reduced to < 85% of rating. 2. When reactor power is < 85% but 50% of rating, the rod cluster control assemblies shall be maintained within +/- 24 steps from their respective banks. If a rod cluster control assembly is misaligned from its bank by more than +/- 24 steps when reactor power is
< 85% but 50%, the rod will be realigned or the core power peaking factors shall be determined within four hours, and TS 3.10.b applied. If the peaking factors are not determined within four hours, the reactor power shall be reduced to < 50% of rating. 3. And, in addition to TS 3.10.e.1 and TS 3.10.e.2, if the misaligned rod cluster control assembly is not realigned within eight hours, the rod shall be declared inoperable.
LCO 3.1.4 part a M02Add proposed Required Actions B.1.1, B.1.2, and B.2 and associated Completion Times M01 Add proposed Required Actions C.1.1, C.1.2, C.2, C.3, C.4, and C.5 and associated Completion TimesM01Add proposed ApplicabilityM02 LCO 3.1.4
part b A CTION B A CTION C f. Inoperable Rod Position Indicator Channels
NOTE: Individual RPIs may be outside their limits for
< 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> following substantial rod movement
- 1. If one individual rod position indicator channel per group is inoperable for one or more groups, then perform either A or B below: (Note: Separate entry condition is allowed for
each inoperable individual rod position indicator.)
A. Verify the position of the rod cluster control indirectly by movable incore detectors each eight hours, or B. Within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> reduce reactor thermal power to 50% of RATED POWER. 2. If more than one individual rod position indicator channel per group are inoperable, then:
A. IMMEDIATELY place the control rods in manual, and B. Once per 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, monitor and record RCS Tavg , and C. Verify the position of the rod by movable incore detectors each 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, and See ITS 3.1.7 Add proposed Required Action D.1M03Add proposed ACTION E M03 LCO 3.1.4 Note See ITS 3.1.7 A CTION D Amendment No. 181 TS 3.10-5 03/24/2005 Page 1 of 5 ITS 3.1.4A01ITS g. Inoperable Rod Limitations
- 1. An inoperable rod is a rod which does not trip or which is declared inoperable under TS 3.10.e or TS 3.10.h. LA02M01Add proposed LCO 3.1.4 and Applicability
- 2. Not more than one inoperable full length rod shall be allowed at any time.
- 3. If reactor operation is continued with one i noperable full length rod, the potential ejected rod worth and associated transient power distribution peaking factors shall be determined by analysis within 30 days unless the rod is made OPERABLE earlier. The analysis shall include due allowance for nonuniform fuel depletion in the neighborhood of the inoperable rod. If the analysis results in a more limiting hypothetical transient than the cases reported in the safety analysis, the plant power level shall be reduced to an analytically determined part power level which is consistent with the safety analysis. made OPERABLE earlier. The analysis shall include due allowance for nonuniform fuel depletion in the neighborhood of the inoperable rod. If the analysis results in a more limiting hypothetical transient than the cases reported in the safety analysis, the plant power level shall be reduced to an analytically determined part power level which is consistent with the safety analysis.
- h. Rod Drop Time h. Rod Drop Time At OPERATING temperature and full flow, the drop time of each full length rod cluster control shall be no greater than 1.8 seconds from loss of stationary gripper coil voltage
to dashpot entry. If drop time is > 1.8 seconds, the rod shall be declared inoperable. At OPERATING temperature and full flow, the drop time of each full length rod cluster control shall be no greater than 1.8 seconds from loss of stationary gripper coil voltage
to dashpot entry. If drop time is > 1.8 seconds, the rod shall be declared inoperable. SR 3.1.4.3 A CTION A Add proposed LCO 3.1.4 and Applicability M04Add proposed Required Actions A.1.1, A.1.2, and A.2 M04M01 A CTION A i. Rod Position Deviation Monitor i. Rod Position Deviation Monitor If the rod position deviation monitor is inoperable, individual rod positions shall be logged at least once per eight hours and after a load change > 10% of rated power or
after > 24 steps of control rod motion. If the rod position deviation monitor is inoperable, individual rod positions shall be logged at least once per eight hours and after a load change > 10% of rated power or
after > 24 steps of control rod motion.
L01j. Quadrant Power Tilt Monitor j. Quadrant Power Tilt Monitor If one or both of the quadrant power tilt monitors is inoperable, individual upper and lower excore detector calibrated outputs and the quadrant tilt shall be logged once per shift and after a load change > 10% of rated power or after > 24 steps of control rod
motion. The monitors shall be set to alarm at 2% tilt ratio. If one or both of the quadrant power tilt monitors is inoperable, individual upper and lower excore detector calibrated outputs and the quadrant tilt shall be logged once per shift and after a load change > 10% of rated power or after > 24 steps of control rod
motion. The monitors shall be set to alarm at 2% tilt ratio.
- k. Core Average Temperature k. Core Average Temperature During steady-state power operation, Tavg , shall be maintained within the limits specified in the COLR, except as provided by TS 3.10.n. During steady-state power operation, Tavg , shall be maintained within the limits specified in the COLR, except as provided by TS 3.10.n. l. Reactor Coolant System Pressure l. Reactor Coolant System Pressure During steady-state power operation, Reactor Coolant System pressure shall be
maintained within the limits specified in t he COLR, except as provided by TS 3.10.n. During steady-state power operation, Reactor Coolant System pressure shall be
maintained within the limits specified in t he COLR, except as provided by TS 3.10.n. See ITS 3.2.4 See ITS 3.4.1 Amendment No. 181 TS 3.10-7 Revised by letter dated 11/03/06 Page 2 of 5 ITS 3.1.4 A01ITS 4.1 OPERATIONAL SAFETY REVIEW APPLICABILITY Applies to items directly related to safety limits and LIMITING CONDITIONS FOR OPERATION.
OBJECTIVE To assure that instrumentation shall be checked, tested, and calibrated, and that equipment and sampling tests shall be conducted at sufficiently frequent intervals to
ensure safe operation.
SPECIFICATION
- a. Calibration, testing, and checking of protective instrumentation channels and testing of logic channels shall be performed as specified in Table TS 4.1-1.
- b. Equipment and sampling tests shall be conducted as specified in Table TS 4.1-2 and TS 4.1-3.
See other ITS SR 3.1.4.2, SR 3.1.4.3
- c. Deleted
- d. Deleted
- e. Deleted Amendment No. 119 TS 4.1-1 04/18/95 Page 3 of 5 TABLE TS 4.1-1 MINIMUM FREQUENCIES FOR CHECKS, CALIBRATIONS AND TEST OF INSTRUMENT CHANNELS Amendment No. 151 Page 2 of 7 02/12/2001 CHANNEL DESCRIPTION CHECK CALIBRATE TEST REMARKS 6. Pressurizer Water Level Each shift Each refueling cycle Monthly 7. Pressurizer Pressure Each shift Each refueling cycle Monthly 8. a. 4-KV Voltage and Frequency Not applicable Each refueling cycle Monthly Reactor protection circuits only b. 4-KV Voltage (Loss of Voltage)
Not applicable Each refueling cycle Monthly Safeguards buses only c. 4-KV Voltage (Degraded Grid)
Not applicable Each refueling cycle Monthly Safeguards buses only 9. Analog Rod Position Each shift(a,b)
Each refueling cycle Each refueling cycle (a) With step counters (b) Following rod motion in excess of 24 steps when computer is out of service 10. Rod Position Bank Counters Each shift(a,b)
Not applicable Each refueling cycle (a) With analog rod position (b) Following rod motion in excess of 24 steps when computer is out of service SR 3.1.4.1 L02 L02See ITS 3.3.5 See ITS 3.3.1 and 3.3.2 L02See ITS 3.1.7 ITS A01 ITS 3.1.4 Page 4 of 5 TABLE TS 4.1-3 MINIMUM FREQUENCIES FOR EQUIPMENT TESTS Amendment No. 125 Page 1 of 1 08/07/96 ITS 3.1.4ITS A01 Page 5 of 5 EQUIPMENT TESTS (1) TEST FREQUENCY 1. Control Rods Rod drop times of all full length rods Partial movement of all
rods not fully inserted in the
core Each REFUELING outage
Quarterly when at or above HOT
STANDBY 1a. Reactor Trip Breakers Independent test (2) shunt and undervoltage trip
attachments Monthly 1b. Reactor Coolant Pump Breakers-Open-Reactor Trip OPERABILITY Each REFUELING outage 1c. Manual Reactor Trip Open trip reactor (3) trip and bypass breaker Each REFUELING outage
- 2. Deleted
- 3. Deleted
- 4. Containment Isolation Trip OPERABILITY Each REFUELING outage 5. Refueling System Interlocks OPERABILITY Prior to fuel movement each REFUELING outage
- 6. Deleted
- 7. Deleted
- 8. RCS Leak Detection OPERABILITY Weekly (4) 9. Diesel Fuel Supply Fuel Inventory (5) Weekly 10. Deleted
- 11. Fuel Assemblies Visual Inspection Each REFUELING outage
- 12. Guard Pipes Visual Inspection Each REFUELING outage 13. Pressurizer PORVs OPERABILITY Each REFUELING cycle 14. Pressurizer PORV Block Valves OPERABILITY Quarterly (6) 15. Pressurizer Heaters OPERABILITY (7) Each REFUELING cycle 16. Containment Purge and Vent Isolation Valves OPERABILITY (8) Each REFUELING cycle
(1) Following maintenance on equipment that could affect the operation of the equipment, tests should be performed to verify OPERABILITY. (2) Verify OPERABILITY of the bypass breaker undervoltage trip attachment prior to placing breaker into service. (3) Using the Control Room push-buttons, independently test the reactor trip breakers shunt trip and undervoltage trip attachments. The test shall also verify the undervoltage trip attachment
on the reactor trip bypass breakers.
(4) When reactor is at power or in HOT SHUTDOWN condition.
(5) Inventory of fuel required in all plant modes.
(6) Not required when valve is administratively closed.
(7) Test will verify OPERABILITY of heaters and availability of an emergency power supply.
(8) This test shall demonstrate that the valve(s) close in 5 seconds.
SR 3.1.4.2 See ITS 3.3.1 See ITS 3.4.15 See ITS 3.4.11 See ITS 3.4.9 See ITS 3.6.3 See ITS 3.6.1 See ITS 4.0 See ITS 3.8.1 and 3.8.3 See ITS 3.6.3 See CTS 3.8.a.11 L03 See ITS 3.3.1 See ITS 3.4.15 See ITS 3.4.9 See ITS 3.6.3 See ITS 3.4.11 See ITS 3.8.1 and 3.8.3 L03 SR 3.1.4.3
DISCUSSION OF CHANGES ITS 3.1.4, ROD GROUP ALIGNMENT LIMITS ADMINISTRATIVE CHANGES A01 In the conversion of the Kewaunee Power Station (KPS) Current Technical Specifications (CTS) to the plant specific Improved Technical Specifications (ITS), certain changes (wording preferences, editorial changes, reformatting, revised numbering, etc.) are made to obtain consistency with NUREG-1431, Rev. 3.0, "Standard Technical Specifications-Westinghouse Plants" (ISTS).
These changes are designated as administrative changes and are acceptable because they do not result in technical changes to the CTS.
MORE RESTRICTIVE CHANGES
M01 CTS 3.10.e.2 states, in part, that when reactor power is < 85% but 50% of rating, the rod cluster control assemblies shall be maintained within +/- 24 steps from their respective banks. CTS 3.10.g.2 states that not more than one inoperable full length rod shall be allowed at any time. CTS 3.10.h states, in part, that at OPERATING temperature and full flow, the drop time of each full length rod cluster control shall be no greater than 1.8 seconds from loss of stationary gripper coil voltage to dashpot entry. ITS 3.1.4 requires all shutdown and control rods and the individual rod position indication to be OPERABLE in MODES 1 and 2 and requires the 24 step alignment limit to be met when < 85% RTP in MODES 1 and 2. This changes the CTS by requiring all shutdown and control rods and the individual rod position indication to be OPERABLE in MODES 1 and 2 and requires the 24 step alignment limit to be met when < 85% RTP in MODES 1 and 2, in lieu of when < 85% RTP and
> 50% RTP.
The purpose of CTS 3.10.e.1 and CTS 3.10.e.2 is to maintain the rods in alignment with their respective banks to provide consistency with the assumption of the safety analyses, to maintain symmetric neutron flux and power distribution profiles, to provide assurance that peaking factors are within acceptable limits, and to assure adequate shutdown margin. The purpose of CTS 3.10.g and 3.10.h are to maintain the potential consequence of accidents consistent with the safety analyses. The proposed change is acceptable because it now states that all shutdown and control rods are required to be OPERABLE in MODES 1 and 2 and that alignment limits must be met in MODES 1 and 2. Additionally, it requires that individual rod position indication, dependent on percent of RTP, to be OPERABLE in MODES 1 and 2. This change is designated as more restrictive because specific LCO requirements and MODES of Applicability are specified.
M02 CTS 3.10.e.1 state, in part, that if a rod cluster control assembly is misaligned from its bank by more than +/- 12 steps when reactor power is
> 85%, then the rod will be realigned or the core power peaking factors shall be determined within four hours and TS 3.10.b applied. If peaking factors are not determined within four hours, the reactor power shall be reduced to < 85% of rating. ITS 3.1.4 ACTION B states that with one rod not within alignment limits when THERMAL POWER is > 85% RTP, to verify SHUTDOWN MARGIN (SDM) or initiate boration to restore SDM to within limits within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, and to reduce THERMAL POWER to < 85% RTP within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. CTS 3.10.e.2 states, in part, that if a rod Kewaunee Power Station Page 1 of 6 DISCUSSION OF CHANGES ITS 3.1.4, ROD GROUP ALIGNMENT LIMITS cluster control assembly is misaligned from its bank by more than +/- 24 steps when reactor power is < 85 % but
> 50%, the rod will be realigned or the core power peaking factors shall be determined within four hours and TS 3.10.b applied. If peaking factors are not determined within four hours, the reactor power shall be reduced to < 50% of rating. ITS 3.1.4 ACTION C states that with one rod not within alignment limits when THERMAL POWER is < 85% RTP, to verify SHUTDOWN MARGIN (SDM) or initiate boration to restore SDM to within limit within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, to reduce THERMAL POWER to < 50% RTP within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, to verify SDM is within the limits specified in the COLR once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, to perform SR 3.2.1.1 and SR 3.2.1.2 (verification that F Q(Z) is within the required limits) within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, to perform SR 3.2.2.1 (verification that is within the required limits) within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> and to re-evaluate safety analyses and confirm results remain valid for duration of operation under these conditions within 5 days. This changes the CTS by requiring the verification of SDM or initiation of boration to restore SDM to within limit within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, reduction of THERMAL POWER to < 85% RTP within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, verification of SDM is within the limits specified in the COLR once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, the performance SR 3.2.1.1 and SR 3.2.1.2 within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, the performance of SR 3.2.2.1within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> and the re-evaluation of the safety analyses and confirmation that the results remain valid for the duration of operation under these conditions within 5 days.
H N F This change is acceptable because verification that the SDM is within its limits or the initiation of boration to restore the SDM to within limits is desirable. In contrast, it is not always desirable or possible to realign the misaligned control rod. Furthermore, if the misaligned rod continues to not meet the applicable alignment limits, in addition to the verification or restoration, the THERMAL POWER must be reduced (which in the case of the 12 step limit could result in meeting the alignment limits), periodic verification of the SDM must be accomplished along with the verification of F Q (Z) and , and an evaluation must be performed to confirm that the accident analyses remain valid. All of these actions ensure that the core design criteria will not be exceeded. Additionally, the Completion Times are commensurate with safe operation of the plant and provides sufficient time to accomplish the Required Actions. This change is designated as more restrictive because more stringent Required Actions and shorter Completion Times have been added that were not in the CTS. H N F M03 CTS 3.10.e.3 states that in addition to TS 3.10.e.1 (CTS 3.10.e.1) and TS 3.10.e.2 (CTS 3.10.e.2) if the misaligned rod cluster control assembly is not realigned within eight hours, the rod shall be declared inoperable. CTS 3.10.e does not contain any requirements if 3.10.e.1 or 3.10.e.2 are not met. Therefore, CTS 3.0.c entry would be required. CTS 3.0.c requires action to be initiated within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and to be in HOT STANDBY (equivalent to ITS MODE 2) in the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. ITS 3.1.4 ACTION D states, that if the Required Action and associated Completion Time of Condition B and C are not met, then be in MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. Additionally, CTS 3.10.e does not contain a requirement for when more than one rod is not within alignment limits. Therefore, CTS 3.0.c entry would also be required for this condition. ITS 3.1.4 ACTION E requires that if more than one rod is not within the alignment limit, then verify SDM is within the
limits specified in the COLR or initiate boration to restore the required SDM to Kewaunee Power Station Page 2 of 6 DISCUSSION OF CHANGES ITS 3.1.4, ROD GROUP ALIGNMENT LIMITS within limits within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and to be in MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. This changes the CTS by requiring the plant to be placed in MODE 3 if the Required Actions and associated Completion Time of B or C are not met (ITS 3.1.4 ACTION D) and adding a new ACTION (ITS 3.1.4 ACTION E).
This change is acceptable because the Completion Time is consistent with safe operation under the specified Condition, considering the OPERABLE status of the redundant systems or features, a reas onable time for repairs or replacement, and the low probability of a DBA occurring during the allowed Completion Times.
Allowing 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> to verify SDM is within the limits specified in the COLR or initiation of boration to restore the required SDM to within limits and 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> to be in MODE 3 ensures a unit shutdown is commenced and completed within a reasonable period of time upon failure to restore the SDM to within limits within the allowed Completion Times. This change is designated as more restrictive because the time to exit the Applicability of the LCO has been reduced.
M04 CTS 3.10.g.2 states that not more than one inoperable full length rod shall be allowed at any time. As a result, if more than one full length rod is inoperable, then LCO 3.0.c would be entered which requires action to be initiated within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, to be in HOT STANDBY (equivalent to ITS MODE 2) within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and to be in HOT SHUTDOWN (equivalent to ITS MODE 3) within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. CTS 3.10.g.3 states, in part, that with one inoperable full length rod the potential ejected rod worth and associated transient power distribution peaking factors shall be determined by analysis within 30 days.
ITS 3.1.4 requires that with one or more rods inoperable to verify the SDM is within the limits specified in the COLR or to initiate boration to restore the SDM to within limits within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and to be in MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. This changes the CTS by requiring verification or restoration of the SDM and requiring the unit to be in MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
The purpose of CTS 3.10.g.2 and 3.10.g.3 is to maintain the potential ejected rod worth and associated transient power distribution factor consistent with the safety analysis. This change is acceptable because it is not expected that more than one control rod will become misaligned from its group average position. When one or more control rods are misaligned, there is a potential for reduced SDM.
Therefore, SDM must be evaluated. One hour allows the operator adequate time to determine SDM. Restoration of the required SDM, if necessary, requires increasing the RCS boron concentration to provide negative reactivity. The required Completion Time of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> for initiating boration is reasonable, based on the time required for potential xenon redistribution, the low probability of an accident occurring, and the steps required to complete the action. This allows the operator sufficient time to align the required valves and start the boric acid pumps. Boration will continue until the required SDM is restored. This change is acceptable because it is consistent with the requirements of the assumptions of the safety analyses to be within the SDM limit. Additionally, the requirement to be in MODE 2 is not required since the ITS requires the unit to be in MODE 3 in the same time (i.e., 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />). The change has been designated as more restrictive because the ITS requires verification or restoration of the SDM within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> and the unit to be placed in MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> in lieu of the CTS requirement to determine the potential ejected rod worth and associated transient Kewaunee Power Station Page 3 of 6 DISCUSSION OF CHANGES ITS 3.1.4, ROD GROUP ALIGNMENT LIMITS power distribution peaking factors within 30 days for one inoperable full length rod.
RELOCATED SPECIFICATIONS None
REMOVED DETAIL CHANGES LA01 (Type 1 - Removing Details of System Design and System Description, Including Design Limits) CTS 3.10.e states, in part, that the magnitude of an indicated rod misalignment may be determined by comparison of the respective bank demand counter to the analog individual rod position indicator, the rod position on the plant process computer, or through the conditioning module output voltage via a correlation of rod position vs. voltage. ITS 3.1.4 does not contain this statement. This changes the CTS by moving the description of how to determine the magnitude of the rod misalignment to the Bases.
The removal of these details which relate to the system design from the Technical Specification is acceptable because this type of information is not necessary to be included to provide adequate protection of public health and safety. This change is acceptable because the removed information will be adequately controlled in the ITS Bases. Changes to the Bases are controlled by the Technical Specifications Bases Control Program in Chapter 5. This program provides for the evaluation of changes to ensure the Bases are properly controlled. This change is designated as a less restrictive removal of detail change because the information relating to system design is being removed from the Technical Specifications.
LA02 (Type 1 - Removing Details of System Design and System Description, Including Design Limits) CTS 3.10.g.1 states, in part, that an inoperable rod is a rod which does not trip or which is declared inoperable. ITS 3.1.4 does not contain this statement. This changes the CTS by moving the detail describing an inoperable rod to the Bases.
The removal of these details which relate to the system design from the Technical Specifications is acceptable because this type of information is not necessary to be included to provide adequate protection of public health and safety. This change is acceptable because the removed information will be adequately controlled in the ITS Bases. Changes to the Bases are controlled by the Technical Specifications Bases Control Program in Chapter 5. This program provides for the evaluation of changes to ensure the Bases are properly controlled. This change is designated as a less restrictive removal of detail change because the information relating to system design is being removed from the Technical Specifications.
Kewaunee Power Station Page 4 of 6 DISCUSSION OF CHANGES ITS 3.1.4, ROD GROUP ALIGNMENT LIMITS LESS RESTRICTIVE CHANGES L01 (Category 7 - Relaxation of Surveillance Frequency)
CTS 3.10.i requires that if the rod position deviation monitor is inoperable, individual rod positions shall be logged at least once per eight hours and after a load change > 10% of rated power or after > 24 steps of control rod motion. ITS SR 3.1.4.1 requires verification that the individual rod positions are within the alignment limits every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. This changes the CTS by eliminating the requirement to log the individual rod positions once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and after a load change > 10% of rated power or after > 24 steps of control rod motion when the Rod Position Deviation Monitor is inoperable.
The purpose of CTS 3.10.i is to periodically verify that the rods are within the alignment limits specified in the LCO. This change is acceptable because the Surveillance Frequency has been evaluated to ensure that it provides an acceptable level of equipment reliability. Increasing the Frequency of rod position verification when the Rod Position Deviation Monitor is inoperable is unnecessary, since an inoperability of the alarm does not increase the probability that the rods are misaligned. The Rod Position Deviation Monitor alarm is for indication only. Its use is not credited in any safety analyses. This change is designated as less restrictive because Surveillances will be performed less frequently under the ITS than under the CTS.
L02 (Category 7 - Relaxation of Surveillance Frequency) Note (b) to CTS Table TS 4.1-1 Channel Description 9 requires an Analog Rod Position check following rod motion in excess of 24 steps when the computer is out of service. Note (b) to CTS TS Table 4.1-1 Channel Description 10 requires a Rod Position Bank Counters check following rod motion in excess of 24 steps when the computer is out of service. ITS SR 3.1.4.1 requires a verification that individual rod positions are within alignment every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. This changes the CTS by not requiring an Analog Rod Position check and a Rod Position Bank Counters check following rod motion in excess of 24 steps when the computer is out of service.
The purpose of CTS Table TS 4.1-1 Channel Descriptions 9 and 10 Channel Checks is to verify that the rods are within the alignment limits. This change is acceptable because the verification of the rod position following rod motion in excess of 24 steps when the computer is out of service is unnecessary. An inoperable computer does not increase the probability that the rods are misaligned. The routine 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Frequency (ITS SR 3.1.4.1) continues to ensure that the control rods are aligned properly. Furthermore, ITS 3.1.7 Required Action A.1 requires the position of a rod with an inoperable position indicator to be verified once within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after moving the rod in excess of 24 steps. Thus, any response determined necessary by plant personnel due to an inoperable computer is more appropriately controlled by plant procedures, not Technical Specifications. This change is designated as less restrictive because Surveillances will be performed less frequently under ITS than under the CTS.
L03 (Category 5 - Deletion of Surveillance Requirement)
Note 1 to CTS Table TS 4.1-3 requires, in part, that the Control Rods be tested to verify OPERABILITY following maintenance on equipment that could affect the Kewaunee Power Station Page 5 of 6 DISCUSSION OF CHANGES ITS 3.1.4, ROD GROUP ALIGNMENT LIMITS Kewaunee Power Station Page 6 of 6 operation. ITS 3.1.4 does not include this requirement. This changes the CTS by eliminating a post-maintenance Surveillance Requirement.
This change is acceptable because the deleted Surveillance Requirement is not necessary to verify that the equipment used to meet the LCO can perform its required functions. Thus, appropriate equipment continues to be tested in a manner and frequency necessary to give confidence that the equipment can perform its assumed safety function.
Whenever, the OPERABILITY of a system or component has been affected by repair, maintenance, modification, or replacement of a component, post maintenance testing is required to
demonstrate the OPERABILITY of the system or component. This is described in the Bases for ITS SR 3.0.1 and required under SR 3.0.1. In addition, the requirement of 10 CFR 50, Appendix B, Section XI (Test Control), provides adequate controls for test programs to ensure that testing incorporates applicable acceptance criteria. Compliance with 10 CFR 50, Appendix B is required under the unit operating license. As a result, post-maintenance testing will continue to be performed and an explicit requirement in the Technical Specifications is not necessary. This change is designated as less restrictive because a Surveillance which is required in the CTS will not be performed in the ITS.
Improved Standard Technical Specifications (ISTS) Markup and Justification for Deviations (JFDs)
Rod Group Alignment Limits 3.1.4 WOG STS 3.1.4-1 Rev. 3.0, 03/31/04 CTS 3.1 REACTIVITY CONTROL SYSTEMS
3.1.4 Rod Group Alignment Limits
LCO 3.1.4 All shutdown and control rods shall be OPERABLE. 3.10.g, 3.10.h AND Individual indicated rod positions shall be within 12 steps of their group step counter demand position.
INSERT 1 3.10.e.1, 3.10.e.2 as follows:
1 DOC M01 APPLICABILITY: MODES 1 and 2.
ACTIONS 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.
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />
6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> B. One rod not within alignment limits.
B.1 Restore rod to within alignment limits.
OR B.2.1.1 Verify SDM to be within the limits specified in the COLR. OR 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> when THERMAL POWER is 85% RTP is 3 s 4 4 5 4 2 is3.10.g.3, DOC M04 3.10.e.1 3.1.4 CTS 1 INSERT 1 a. With THERMAL POWER 85% RTP, within 12 steps from their respective banks; and 3.10.e.1 3.10.e.2 b. With THERMAL POWER < 85% RTP, within 24 steps from their respective banks.
NOTE------------------------------------------------- Individual rod position indicators may be outside of their limits for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> following substantial rod movement.
3.10.e Note
Insert Page 3.1.4-1 Rod Group Alignment Limits 3.1.4 WOG STS 3.1.4-2 Rev. 3.0, 03/31/04 CTS ACTIONS (continued)
CONDITION REQUIRED ACTION COMPLETION TIME
B.2.1.2 Initiate boration to restore SDM to within limit.
AND B.2.2 Reduce THERMAL POWER to 75% RTP.
AND B.2.3 Verify SDM is within the limits specified in the COLR. AND B.2.4 Perform SR 3.2.1.1 and SR 3.2.1.2.
AND B.2.5 Perform SR 3.2.2.1.
AND B.2.6 Re-evaluate safety analyses and confirm results remain valid for duration of operation under these conditions.
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />
2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />
Once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />
72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />
72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />
5 days C. Required Action and associated Completion Time of Condition B not met. C.1 Be in MODE 3.
6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> D. More than one rod not within alignment limit.
D.1.1 Verify SDM is within the limits specified in the COLR.
OR 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> 3.10.e.1 3 4 s 4 5 4< 85INSERT 2 5 5 3.10.e.3 D D 5or C E E 5DOC M03 3.1.4 CTS 5 INSERT 2 C. One rod not within alignment limits when THERMAL POWER is
< 85% RTP.
C.1.1 Verify SDM is within limits specified in the COLR.
OR C.1.2 Initiate boration to restore SDM to within limits.
AND C.2 Reduce THERMAL POWER to < 50% RTP.
AND C.3 Verify SDM is within limits specified in the COLR.
AND C.4 Perform SR 3.2.1.1 and SR 3.2.1.2.
AND C.5 Perform SR 3.2.2.1.
AND C.6 Re-evaluate safety analyses and confirm
results remain valid for duration of operation under these conditions.
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />
2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />
Once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />
72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />
72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />
5 days 3.10.e.2
Insert Page 3.1.4-2 Rod Group Alignment Limits 3.1.4 WOG STS 3.1.4-3 Rev. 3.0, 03/31/04 CTS ACTIONS (continued)
CONDITION REQUIRED ACTION COMPLETION TIME
D.1.2 Initiate boration to restore required SDM to within
limit.
AND D.2 Be in MODE 3.
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />
6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> 5DOC M03 E 3 s E 5 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.1.4.1 Verify individual rod positions within alignment limit.
12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> SR 3.1.4.2 Verify rod freedom of movement (trippability) by moving each rod not fully inserted in the core 10 steps in either direction.
92 days SR 3.1.4.3 Verify rod drop time of each rod, from the fully withdrawn position, is [2.2] seconds from the beginning of decay of stationary gripper coil voltage to dashpot entry, with:
- a. Tavg 500°F and
- b. All reactor coolant pumps operating.
Prior to criticality after each removal of the reactor head Table 4.1-1 Channel Description 9 and 10 Table 4.1-3
Equipment Test 1 3.10.h.1, Table 4.1-3
Equipment Test 1 1.8 6 JUSTIFICATION FOR DEVIATIONS ITS 3.1.4, ROD GROUP ALIGNMENT LIMITS Kewaunee Power Station Page 1 of 2 1. LCO 3.1.4 (2nd part) has been modified to incorporate a Kewaunee Power Station (KPS) specific allowance. This change to the LCO has been made consistent with the allowance in License Amendment 51, dated December 28, 1983 (ADAMS Accession Number ML020740166), with one exception. The CTS does not require alignment limits to be met when < 50% RTP, as shown in CTS 3.10.e.2. However, as part of converting to the ITS, KPS will require alignment limits to be met at all times when in MODES 1 and 2. That is, the
24 step limit that is currently required when <
85% and > 50% RTP will be applicable in MODE 1 when < 85% RTP and in MODE
- 2.
- 2. Changes are made to be consistent with the format of the ITS. The Required Action normally states that the parameter shall be "within limits." 3. Typographical/grammatical error corrected.
- 4. ISTS 3.1.4 Required Action B.1 requires restoration of a rod not within alignment limits within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> or performance of a number of other actions, such as verification of SHUTDOWN MARGIN, reduction in reactor power, measurement of hot channel factors, and re
-evaluation of the safety analyses. The Writer's Guide for Improved Standard Technical Specifications, TSTF
-GG-05-01, Section 4.1.6.g states, "A Required Action which requires restoration, such that the Condition is no longer met, is considered superfluous. It is only included if it would be the only Required Action for the Condition or it is needed for presentation clarity." Neither exception applies in this case. In fact, the inclusion of Required Action B.1 requires an additional level of indenting and numbering for the remaining Required Actions in Condition B, which reduces its clarity. Therefore, Required Action B.1 is deleted and the subsequent Required Actions renumbered.
- 5. ISTS 3.1.4 ACTION B has been split into two ACTIONS, based on the KPS specific rod group alignment limits. As discussed in JFD 1, LCO 3.1.4 (2nd part) has been modified to be consistent with KPS License Amendment 51. The KPS CTS requires the rod alignment to be within 12 steps when
> 85% RTP, but only 24 steps when < 85% RTP. Therefore, the following changes have been made due to this difference:
- a. ISTS 3.1.4 Condition B has been modified to only be applicable when THERMAL POWER is
> 85% RTP. ITS 3.1.4 ACTION B will now provide the actions when the
> 85% RTP alignment limit (12 steps) is not met. For ITS ACTION B, only ISTS 3.1.4 Required Actions B.2.1.1, B.2.1.2, and B.2.2 are being maintained (note that ISTS 3.1.4 Required Action B.1 has been deleted as discussed in JFD 4). ISTS 3.1.4 Required Action B.2.2 (ITS 3.1.4 Required Action B.2) has been modified to require reduction in THERMAL POWER to < 85% RTP. Thus, once power is reduced to < 85% RTP, the Condition B entry requirements are not met. Furthermore, once power is reduced, a new alignment limit, 24 steps, is applicable. Therefore, the follow
-
on Required Actions in the ISTS (ISTS 3.1.4 Required Actions B.2.3, B.2.4, B.2.5, and B.2.6) are not applicable and are not included in ITS 3.1.4 ACTION B.
JUSTIFICATION FOR DEVIATIONS ITS 3.1.4, ROD GROUP ALIGNMENT LIMITS Kewaunee Power Station Page 2 of 2 b. A new ACTION has been added (ITS 3.1.4 ACTION C) to cover not meeting the < 85% RTP alignment limit. ITS 3.1.4 Condition C covers the condition of one rod not within alignment limits when THERMAL POWER is < 85% RTP.
The proposed Required Actions for this Condition are consistent with the Required Actions of ISTS 3.1.4 ACTION B, except the restore Required Action is not included (as described in JFD 4) and the power reduction value in ITS 3.1.4 Required Action C.2 is < 50% RTP (in lieu of the ISTS value of < 75% RTP), consistent with the current KPS CTS.
In addition, due to the above changes (the addition of new ACTION C),
subsequent Conditions and Required Actions have been renumbered.
- 6. The ISTS contains bracketed information and/or values that are generic to all Westinghouse vintage plants. The brackets are removed and the proper plant specific information/value is provided. This is acceptable since the generic specific information/value is revised to reflect the current plant design.
Improved Standard Technical Specifications (ISTS) Bases Markup and Bases Justification for Deviations (JFDs)
Rod Group Alignment Limits B 3.1.4 WOG STS B 3.1.4-1 Rev. 3.0, 03/31/04 B 3.3 INSTRUMENTATION
B 3.1.4 Rod Group Alignment Limits
BASES BACKGROUND The OPERABILITY (i.e., 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," 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 Plants" (Ref. 2). INSERT 1 1 Mechanical or electrical failures may cause a control or shutdown rod to become inoperable or to become misaligned from its group. 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, 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 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 e inch) at a time, but at varying rates (steps per minute) depending on the signal output from the Rod Control System. 2 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. A group consists of two or more RCCAs that are electrically paralleled to step simultaneously. If a bank of RCCAs consists of two groups, the groups are moved in a staggered fashion, but always within one step of each other. All units have four control banks and at least two shutdown banks.
2Kewaunee Power Station (KPS) has B 3.1.4 1 INSERT 1 USAR GDC 6, "Reactor Core Design," GDC 7, "Suppression of Power Oscillations," GDC 27, "Redundancy of Reacti vity Control," GDC 28, "Reactivity Hot Shutdown Capability," GDC 29, "Reactivity Shutdown Capability," and
GDC 30, "Reactivity Holddown Capability"
Insert Page B 3.1.4-1 Rod Group Alignment Limits B 3.1.4 WOG STS B 3.1.4-2 Rev. 3.0, 03/31/04 BASES BACKGROUND (continued)
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 Digital Rod Position Indication (DRPI) 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 +/-
e 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 DRPI System provides a highly accurate indication of actual 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. To increase the reliability of the system, the inductive coils are connected alternately to data system A or B. Thus, if one data system fails, the DRPI will go on half accuracy. The DRPI System is capable of monitoring rod position within at least +/- 12 steps with either full accuracy or half accuracy.
I I Individual 2 control 7 5/8 2 2INSERT 3 INSERT 2 B 3.1.4 2 INSERT 2 The readout of the Bank Demand Position Indication System is in the form of an add and subtract counter reading. There is one display for each rod group.
2 INSERT 3
an analog signal that is proportional to the actual control rod position. This is accomplished by using an electrical coil stack linear variable differential
transformer placed above the stepping mec hanism of the control rod magnetic jacks which are external to the pressure housing. When the control rod is at the bottom of the core, the magnetic coupling between the primary and secondary windings is small and induces a small voltage in the secondary winding. As the control rod raises, the lift rod causes an increase in magnetic coupling which in turn provides an analog signal proportional to the control rod position. The individual rod position indicator channels are sufficiently accurate to detect a rod
+ 12 steps away from its demand position.
Insert Page B 3.1.4-2 Rod Group Alignment Limits B 3.1.4 WOG STS B 3.1.4-3 Rev. 3.0, 03/31/04 BASES APPLICABLE Control rod misalignment accidents are analyzed in the safety analysis SAFETY (Ref. 3). The acceptance criteria for addressing control rod inoperability ANALYSES or misalignment are that:
- a. There be no violations of:
- 41. Specified acceptable fuel design limits or
- 42. Reactor Coolant System (RCS) pressure boundary integrity and
- b. The core remains subcritical after accident transients.
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.
Two types of analysis are performed in regard to static rod misalignment (Ref. 4). With control banks at their insertion limits, one type of analysis considers the case when any one rod is completely inserted into the core. The second 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.
Another type of misalignment occurs if one RCCA fails to insert upon a reactor trip and remains stuck fully wi thdrawn. 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).
INSERT 6 2 2 5INSERT 5 2INSERT 4 A statically misaligned 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.
B 3.1.4 2 INSERT 4 There are three RCCA misalignment acci dents which are analyzed including one or more dropped RCCAs, a dropped RCCA bank, and a statically misaligned RCCA (Ref. 4).
2 INSERT 5
when THERMAL POWER is 85% RTP or by 24 steps when THERMAL POWER is < 85% RTP
2 INSERT 6 For the dropped RCCA(s) or dropped RCCA bank misalignment accidents, a negative reactivity insertion will result. Power will be reestablished either by reactivity feedback or control bank withdrawal. Following plant stabilization, normal rod retrieval or shutdown procedures are followed. For dropped RCCA events in the automatic rod control mode, the Rod Control System detects the drop in power and initiates control bank withdrawal. In all cases, the minimum departure from nucleate boiling ratio (DNBR) remains above the limit value.
Insert Page B 3.1.4-3 Rod Group Alignment Limits B 3.1.4 WOG STS B 3.1.4-4 Rev. 3.0, 03/31/04 BASES APPLICABLE SAFETY ANALYSES (continued)
Continued operation of the reactor with a misaligned control rod is allowed if the heat flux hot channel factor ( F Q(Z)) and the nuclear enthalpy hot channel factor () 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 F Q (Z) and F must be verified directly by incore mapping.
Bases Section 3.2 (Power Distribution Limits) contains more complete discussions of the relation of F Q (Z) and F to the operating limits.
H N FH NH N5 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).
LCO The limits on shutdown or control rod alignments ensure that the assumptions in the safety analysis will remain valid. The requirements on control rod OPERABILITY ensure that upon reactor trip, the assumed reactivity will be available and will be inserted. The control rod OPERABILITY requirements (i.e., trippability) are separate 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 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.
Failure to meet the requirements of this LCO may produce unacceptable power peaking factors and LHRs, or unacceptable SDMs, all of which may constitute initial conditions inconsistent with the safety analysis.
INSERT 8 2 INSERT 8A 6INSERT 7 B 3.1.4 Insert Page B 3.1.4-4 INSERT 7 with THERMAL POWER 85% RTP or within 24 steps of their group step counter demand position when THERMAL POWER is < 85% RTP
INSERT 8
The safety analysis assumes a misalignment of one or more RCCA(s) or, in
some cases, an entire RCCA bank.
INSERT 8A The LCO is modified by a Note stating that individual control rod position indications may be outside the required limits for < 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> following substantial control rod movement. This allows up to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> of thermal soak time to allow the control rod drive shaft to reach thermal equilibrium and thus present a consistent position indication. Substantial rod movement is considered to be 10 or more steps in one direction in <
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. 2 2 6 Rod Group Alignment Limits B 3.1.4 WOG STS B 3.1.4-5 Rev. 3.0, 03/31/04 BASES APPLICABILITY The requirements on RCCA OPER ABILITY 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 limits do not apply because the control rods are bottomed and the reactor is shut down and not producing fission power. In the shutdown MODES, the OPERABILITY of the shutdown and control rods has the potential to affect the required SDM, but this effect can be compensated for by an increase in the boron concentration of the RCS. See LCO 3.1.1, "SHUTDOWN MARGIN (SDM)," for SDM in MODES 3, 4, and 5 and LCO 3.9.1, "Boron Concentration," for boron concentration requirements during refueling.
normally 8 ACTIONS A.1.1 and A.1.2 When one or more rods are inoperable (i.e., untrippable), there is a possibility that the required SDM may be adversely affected. Under these conditions, it is important to determine the SDM, and if it is less than the required value, initiate boration until the required SDM is recovered. The Completion Time of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> is adequate for determining SDM and, if necessary, for initiating emergency boration and restoring SDM.
In this situation, SDM verification must include the worth of the untrippable rod, as well as a rod of maximum worth.
A.2 When one or more rods are inoperable 6If the inoperable rod(s) cannot be restored to OPERABLE status, the plant must be brought to a MODE or condition in which the LCO requirements are not applicable. To achieve this status, the unit must be brought to at least MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
The allowed Completion Time is reasonable, based on operating experience, for reaching MODE 3 from full power conditions in an orderly manner and without challenging plant systems.
B.1 When a rod becomes misaligned, it can usually be moved and is still trippable. If the rod can be realigned within the Completion Time of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, local xenon redistribution during this short interval will not be significant, and operation may proceed without further restriction.
6 Rod Group Alignment Limits B 3.1.4 WOG STS B 3.1.4-6 Rev. 3.0, 03/31/04 BASES ACTIONS (continued)
An alternative to realigning a single misaligned RCCA to the group average position is to align the remainder of the group to the position of the misaligned RCCA. However, this must be done without violating the bank sequence, overlap, and insertion limits specified in LCO 3.1.5, "Shutdown Bank Insertion Limits," and LCO 3.1.6, "Control Bank Insertion Limits." The Completion Time of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> gives the operator sufficient time to adjust the rod positions in an orderly manner.
6 B.2.1.1 and B.2.1.2 With a misaligned rod, SDM must be verified to be within limit or boration must be initiated to restore SDM to within limit.
In many cases, realigning the remainder of the group to the misaligned rod may not be desirable. For example, realigning control bank B to a rod that is misaligned 15 steps from the top of the core would require a significant power reduction, since control bank D must be moved fully in and control bank C must be moved in to approximately 100 to 115 steps.
Power operation may continue with one RCCA trippable but misaligned, provided that SDM is verified within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. The Completion Time of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> represents the time necessary for determining the actual unit SDM and, if necessary, aligning and starting the necessary systems and components to initiate boration.
B.2.2, B.2.3, B.2.4, B.2.5, and B.2.6
For continued operation with a misaligned rod, RTP must be reduced, SDM must periodically be verified within limits, hot channel factors (F Q (Z) and F) must be verified within limits, and the safety analyses must be re-evaluated to confirm continued operation is permissible.
H N Reduction of power to 75% RTP ensures that local LHR increases due to a misaligned RCCA will not cause the core design criteria to be exceeded (Ref. 7). The Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> gives the operator sufficient time to accomplish an orderly power reduction without challenging the Reactor Protection System.
,, C.1.1, and C.1.2 6OPERABLE 6C.2, C.3, C.4, C.5, and C.6 6INSERT 8B 6< 85 INSERT 9 6 B 3.1.4 INSERT 8B 6 when > 85% RTP, THERMAL POWER must be reduced to < 85% RTP. Once power is reduced, the alignment limits are now 24 steps instead of 12 steps. Thus, once power is reduced, Condition B no longer applies. If a rod continues to be misaligned (i.e., it is greater than 24 steps misaligned), then as stated in
Required Actions C.2, C.3, C.4, C.5 and C.6,
6 INSERT 9 when the indicated rod position exceeds 12 steps from their respective banks and < 50% RTP when the indicated rod position exceeds 24 steps from their respective banks
Insert Page B 3.1.4-6 Rod Group Alignment Limits B 3.1.4 WOG STS B 3.1.4-7 Rev. 3.0, 03/31/04 BASES ACTIONS (continued)
When a rod is known to be misaligned, there is a potential to impact the SDM. Since the core conditions can change with time, periodic verification of SDM is required. A Frequency of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> is sufficient to ensure this requirement continues to be met.
Verifying that F Q(Z), as approximated by and , and are within the required limits ensures that current operation at 75% RTP with a rod misaligned is not resulting in power distributions that may invalidate safety analysis assumptions at full power. The Completion Time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> allows sufficient time to obtain flux maps of the core power distribution using the incore flux mapping system and to calculate F Q(Z) and F. )Z(F C Q)Z(F W Q H N FH N Once current conditions have been verified acceptable, time is available to perform evaluations of accident analysis to determine that core limits will not be exceeded during a Design Basis Event for the duration of operation under these conditions. The accident analyses presented in FSAR Chapter 15 (Ref. 5) that may be adversely affected will be evaluated to ensure that the analysis results remain valid for the duration of continued operation under these conditions. A Completion Time of 5 days is sufficient time to obtain the required input data and to perform the analysis.
C.1 When Required Actions cannot be completed within their Completion Time, the unit must be brought to a MODE or Condition in which the LCO requirements are not applicable. To achieve this status, the unit must be brought to at least MODE 2 with K eff < 1.0 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, which obviates concerns about the development of undesirable xenon or power distributions. The allowed Completion Time of 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> is reasonable, based on operating experience, for reaching MODE 3 from full power conditions in an orderly manner and without challenging the plant systems.
D.1.1 and D.1.2
More than one control rod becoming misaligned from its group average position is not expected, and has the potential to reduce SDM. Therefore, SDM must be evaluated. One hour allows the operator adequate time to determine SDM. Restoration of the required SDM, if necessary, requires INSERT 10 < 85 6 14 U 6 D associated 6 6 6 3 E B 3.1.4 6 INSERT 10 when the indicated rod position exceeds 12 steps from their respective banks and < 50% RTP when the indicated rod position exceeds 24 steps from their respective banks
Insert Page B 3.1.4-7 o --
Rod Group Alignment Limits B 3.1.4 WOG STS B 3.1.4-8 Rev. 3.0, 03/31/04 BASES ACTIONS (continued)
increasing the RCS boron concentration to provide negative reactivity, as described in the Bases or LCO 3.1.1. The required Completion Time of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> for initiating boration is reasonable, based on the time required for potential xenon redistribution, the low probability of an accident occurring, and the steps required to complete the action. This allows the operator sufficient time to align the required valves and start the boric acid pumps. Boration will continue until the required SDM is restored.
of 7 D.2 E 6If more than one rod is found to be misaligned or becomes misaligned because of bank movement, the unit conditions fall outside of the accident analysis assumptions. Since automatic bank sequencing would continue to cause misalignment, the unit must be brought to a MODE or Condition in which the LCO requirements are not applicable. To achieve this status, the unit must be brought to at least MODE 2 with K eff < 1.0 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
6 6 3 The allowed Completion Time is reasonable, based on operating experience, for reaching MODE 2 with K eff < 1.0 from full power conditions in an orderly manner and without challenging plant systems.
3 6 SURVEILLANCE SR 3.1.4.1 REQUIREMENTS Verification that individual rod positions are within alignment limits at a Frequency of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> provides a history that allows the operator to detect a rod that is beginning to deviate from its expected position. The specified Frequency takes into account other rod position information that is continuously available to the operator in the control room, so that during actual rod motion, deviations can immediately be detected. INSERT 11 2
SR 3.1.4.2 Verifying each control rod is OPERABLE would require that each rod be
tripped. However, in MODES 1 and 2 with K eff 1.0, tripping each control rod would result in radial or axial power tilts, or oscillations. Exercising each individual control rod every 92 days provides increased confidence that all rods continue to be OPERABLE without exceeding the alignment limit, even if they are not regularly tripped. Moving each control rod by 10 steps will not cause radial or axial power tilts, or oscillations, to occur.
The 92 day Frequency takes into consideration other information 6
B 3.1.4 2 INSERT 11 The verification may be determined by the comparison of the bank demand step counter to the analog IRPI, by the rod position as noted on the plant process computer or through the conditioning module output voltage via a correlation of rod position versus voltage.
Insert Page B 3.1.4-8 Rod Group Alignment Limits B 3.1.4 WOG STS B 3.1.4-9 Rev. 3.0, 03/31/04 BASES SURVEILLANCE REQUIREMENTS (continued)
available to the operator in the control room and SR 3.1.4.1, which is performed more frequently and adds to the determination of OPERABILITY of the rods. Between required performances of SR 3.1.4.2 (determination of control rod OPERABILITY by movement), if a control rod(s) is discovered to be immovable, but remains trippable, the control rod(s) is considered to be OPERABLE. At any time, if a control rod(s) is immovable, a determination of the trippability (OPERABILITY) of the control rod(s) must be made, and appropriate action taken.
Verification of rod drop times allows the operator to determine that the maximum rod drop time permitted is consistent with the assumed rod drop time used in the safety analysis. Measuring rod drop times prior to reactor criticality, after reactor vessel head removal, ensures that the reactor internals and rod drive mechanism will not interfere with rod motion or rod drop time, and that no degradation in these systems has occurred that would adversely affect control rod motion or drop time. This testing is performed with all RCPs operating and the average moderator
temperature 500°F to simulate a reactor trip under actual conditions.
This Surveillance is performed during a plant outage, due to the plant conditions needed to perform the SR and the potential for an unplanned plant transient if the Surveillance were performed with the reactor at
power. REFERENCES 1. 10 CFR 50, Appendix A, GDC 10 and GDC 26.
1
- 2. 10 CFR 50.46. USAR, Sections 3.1.2.1, 3.1.2.2, 3.1.2.3, 3.1.2.4, 3.1.2.5, and 3.1.2.6.
- 3. FSAR, Chapter [15].
- 4. FSAR, Chapter [15].
- 5. FSAR, Chapter [15].
U U U 2 4 14Section 14.1.3 Section 14.1 2 4 2 4 6. FSAR, Chapter [15].
- 7. FSAR, Chapter [15].
2 4 JUSTIFICATION FOR DEVIATIONS ITS 3.1.4 BASES, ROD GROUP ALIGNMENT LIMITS
- 1. ISTS 3.1.4 Bases Background references General Design Criteria. Kewaunee Power Station (KPS) was designed prior to promulgation of 10 CFR 50, Appendix A. Therefore, ITS 3.1.4 Bases Background has been revised to discuss the design standards used by KPS. Additionally, bases references to 10 CFR 50, Appendix A have been replaced with references to the appropriate section of the USAR.
Subsequent reference numbers have been renumbered.
- 2. Changes are made (additions, deletions, and/or changes) to the ISTS Bases which reflect the plant specific nomenclature, number, reference, system description, analysis, or licensing basis description.
- 3. The punctuation corrections have been made consistent with the Writer's Guide from the Improved Technical Specifications, TSTF-GG-05-01, Section 5.1.3.
- 4. The ISTS contains bracketed information and/or values that are generic to all Westinghouse vintage plants. The brackets are removed and the proper plant specific information/value is provided. This is acceptable since the generic specific information/value is revised to reflect the current plant design.
- 5. The discussion of the Required Actions when the LCO is not met has been deleted since it is not appropriate in the Applicable Analyses Section. This information is adequately discussed in the Bases for ACTIONS B.2, B.3, B.4, B.5, B.6, C.2, C.3, C.4, C.5 and C.6.
- 6. Changes made to be consistent with the Specification.
- 7. Typographical/grammatical error corrected.
- 8. The word "normally" has been added since the shutdown banks are required by ITS LCO 3.1.5 to be withdrawn to their insertion limits prior to entering MODE 2 (i.e., in MODE 3). Thus the rods are not bottomed all the time in MODE 3.
Kewaunee Power Station Page 1 of 1 Specific No Significant Haza rds Considerations (NSHCs)
DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATIONS ITS 3.1.4, ROD GROUP ALIGNMENT LIMITS There are no specific NSHC discussions for this Specification.
Kewaunee Power Station Page 1 of 1 ATTACHMENT 5 ITS 3.1.5, SHUTDOWN BANK INSERTION LIMITS Current Technical Specification (CTS) Markup and Discussion of Changes (DOCs)
A01 ITS 3.1.5ITS c. Quadrant Power Tilt Limits
- 1. Except for physics tests, whenever the indicated quadrant power tilt ratio > 1.02, one of the following actions shall be taken within two hours:
A. Eliminate the tilt.
B. Restrict maximum core power level 2% for every 1% of indicated power tilt ratio
> 1.0. 2. If the tilt condition is not eliminated after 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, then reduce power to 50% or lower.
- 3. Except for Low Power Physics Tests, if the indicated quadrant tilt is > 1.09 and there is simultaneous indication of a misaligned rod:
A. Restrict maximum core power level by 2% of rated values for every 1% of indicated power tilt ratio > 1.0.
B. If the tilt condition is not eliminated within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, then the reactor shall be brought to a minimum load condition (30 Mwe). 4. If the indicated quadrant tilt is > 1.09 and there is no simultaneous indication of rod misalignment, then the reactor shall immediately be brought to a no load condition
( 5% reactor power).
- d. Rod Insertion Limits
- 1. The shutdown rods shall be withdrawn to within the limits, specified in the COLR, when the reactor is critical or approaching criticality.
- 2. The control banks shall be limited in physical insertion; insertion limits are specified in the COLR. If any one of the control bank insertion limits is not met:
A. Within one hour, initiate boration to restore control bank insertion to within the limits specified in the COLR, and B. Restore control bank insertion to within the limits specified in the COLR within two hours of exceeding the insertion limits.
C. If any one of the conditions of TS 3.10.d.2.A or TS 3.10.d.2.B cannot be met, then withinone hour action shall be initiated to:
- Achieve HOT STANDBY within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />
- Achieve HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />
- 3. Insertion limit does not apply during physics tests or during periodic exercise of individual rods. However, the shutdown margin, as specified in the COLR, must be maintained except for the Low Power Physics Test to measure control rod worth and shutdown margin. For this test, the reactor may be critical with all but one high worth
rod inserted. L01Add proposed ACTIONS A and BA02 A pplicabilit y LCO 3.1.5 See ITS 3.1.8 See ITS 3.1.8 A pplicabilit y Note Add proposed SR 3.1.5.1 M01See ITS 3.1.6 See ITS 3.2.4 Amendment No. 165 TS 3.10-4 03/11/2003 Page 1 of 1 DISCUSSION OF CHANGES ITS 3.1.5, SHUTDOWN BANK INSERTION LIMITS ADMINISTRATIVE CHANGES A01 In the conversion of the Kewaunee Power Station (KPS) Current Technical Specifications (CTS) to the plant specific Improved Technical Specifications (ITS), certain changes (wording preferences, editorial changes, reformatting, revised numbering, etc.) are made to obtain consistency with NUREG-1431, Rev. 3.0, "Standard Technical Specifications-Westinghouse Plants" (ISTS).
These changes are designated as administrative changes and are acceptable because they do not result in technical changes to the CTS.
A02 CTS 3.10.d.1 requires the shutdown rods to be withdrawn to within the limits specified in the COLR when the reactor is critical or approaching criticality. ITS 3.1.5 requires each shutdown bank to be within the insertion limits specified in the COLR in MODES 1 and 2. This changes the CTS by clearly specifying the MODES in which the LCO is required.
The CTS condition of "reactor is critical" normally occurs only in ITS MODE 1 and MODE 2 with k eff > 1.0. The CTS condition of "approaching criticality" normally occurs only in MODE 2 with k eff < 1.0. Therefore, since the ITS 3.1.5 MODES 1 and 2 are equivalent to the CTS conditions, this change is acceptable and is designated as administrative.
MORE RESTRICTIVE CHANGES
M01 CTS 3.10.d.1 requires the shutdown rods to be withdrawn to within the limits specified in the COLR, but does not provide a Surveillance Requirement to verify that the shutdown rods are within the limits specified in the COLR. ITS SR 3.1.5.1 requires verification that the shutdown banks are within the insertion limits specified in the COLR every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. This changes the CTS by adding a
new Surveillance Requirement to verify that the shutdown banks are within the insertion limits specified in the COLR every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
The purpose of ITS SR 3.1.5.1 is to verify that the shutdown banks are within their insertion limits, available to shut down the reactor, and that the required SHUTDOWN MARGIN (SDM) will be maintained following a reactor trip. The 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Frequency takes into account other information that is available in the control room for monitoring the status of the shutdown rods. This change is designated as more restrictive because a new Surveillance Requirement has been added to verify that the shutdown banks are within the insertion limits specified in the COLR every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
RELOCATED SPECIFICATIONS None
Kewaunee Power Station Page 1 of 2 DISCUSSION OF CHANGES ITS 3.1.5, SHUTDOWN BANK INSERTION LIMITS Kewaunee Power Station Page 2 of 2 REMOVED DETAIL CHANGES None
LESS RESTRICTIVE CHANGES
L01 (Category 4 - Relaxation of Required Action)
CTS 3.10.d.1 does not provide any explicit time to restore the shutdown rods to within their limits. As a result, LCO 3.0.c would be entered, which requires action to be initiated within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, to be in HOT STANDBY (equivalent to ITS MODE 2) within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and in HOT SHUTDOWN (equivalent to ITS MODE 3) within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. Under similar conditions, ITS 3.1.5 ACTION A provides one hour to either verify that the SDM is within the limits specified in the COLR or to initiate boration to restore the SDM to within limits and 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> to restore the shutdown banks to within limits. Additionally, ITS 3.1.5 ACTION B provides 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> to be in MODE 3 if any Required Action and associated Completion Time of ACTION A are not met. This changes the CTS by providing specific ACTIONS when the shutdown banks are not within the limits specified in the COLR.
The purpose of CTS 3.10.d.1 is to ensure that the shutdown rods are within limits specified in the COLR. This change is acceptable because the Required Actions are used to establish remedial measures that must be taken in response to the shutdown rods not being within the limits established in the COLR because the SDM may be significantly reduced. ITS 3.1.5 Required Action A.2 provides 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> in lieu of the 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> in CTS 3.10.d.1 to restore the shutdown bank to within limits. This is acceptable because ITS 3.1.5 Required Action A.2 provides sufficient time for evaluating and repairing minor problems without allowing the plant to remain in an unacceptable condition for an extended period of time. The Completion Time of ITS 3.1.5 Required Action B.1 provides 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> to be in MODE 3 which is a reasonable time, based on operating experience, to reach the required MODE from full power conditions in an orderly manner and without challenging the plant systems. Additionally, since ITS 3.1.5 Required Action B.1 requires the unit to be in MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, there is no need to maintain the requirement to be in MODE 2 within the same 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. This change is designated as less restrictive because more time is provided in the ITS to restore the shutdown banks to within limits prior to requiring a unit shutdown.
Improved Standard Technical Specifications (ISTS) Markup and Justification for Deviations (JFDs)
Shutdown Bank Insertion Limits 3.1.5 WOG STS 3.1.5-1 Rev. 3.0, 03/31/04 CTS 3.1 REACTIVITY CONTROL SYSTEMS
3.1.5 Shutdown
Bank Insertion Limits
LCO 3.1.5 Each shutdown bank shall be within insertion limits specified in the COLR. 3.10.d.1 APPLICABILITY: MODES 1 and 2.
3.10.d.1 ------------------------------------------NOTE----------------------------------------------- This LCO is not applicable while performing SR 3.1.4.2.
3.10.d.3 --------------------------------------------------------------------------------------------------
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME
A. One or more shutdown banks not within limits.
A.1.1 Verify SDM is within the limits specified in the COLR. OR A.1.2 Initiate boration to restore SDM to within limit.
AND A.2 Restore shutdown banks to within limits.
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />
2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> B. Required Action and associated Completion Time not met.
B.1 Be in MODE 3.
6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> DOC L01 DOC L01 Shutdown Bank Insertion Limits 3.1.5 WOG STS 3.1.5-2 Rev. 3.0, 03/31/04 CTS SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.1.5.1 Verify each shutdown bank is within the insertion limits specified in the COLR.
12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> DOC M01 JUSTIFICATION FOR DEVIATIONS ITS 3.1.5, SHUTDOWN BANK INSERTION LIMITS None Kewaunee Power Station Page 1 of 1 Improved Standard Technical Specifications (ISTS) Bases Markup and Bases Justification for Deviations (JFDs)
Shutdown Bank Insertion Limits B 3.1.5 WOG STS B 3.1.5-1 Rev. 3.0, 03/31/04 B 3.1 REACTIVITY CONTROL SYSTEMS
B 3.1.5 Shutdown Bank Insertion Limits
BASES BACKGROUND The insertion limits of the shutdown and control rods are initial assumptions in all safety analyses that assume rod insertion upon reactor trip. The insertion limits directly affect core power and fuel burnup distributions and assumptions of available ejected rod worth, SDM and initial reactivity insertion rate.
The applicable criteria for these reactivity and power distribution design requirements are 10 CFR 50, Appendix A, GDC 10, "Reactor Design," GDC 26, "Reactivity Control System Redundancy and Protection," GDC 28, "Reactivity Limits" (Ref. 1), and 10 CFR 50.46, "Acceptance Criteria for Emergency Core Cooling Systems for Light Water Nuclear Power Reactors" (Ref. 2). Limits on control rod insertion 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. INSERT 1 1 The rod cluster control assemblies (RCCAs) are divided among control banks and shutdown banks. Each bank may be further subdivided into two groups to provide for precise reactivity control. A group consists of two or more RCCAs that are electrically paralleled to step simultaneously. A bank of RCCAs consists of two groups that are moved in a staggered fashion, but always within one step of each other. All plants have four control banks and at least two shutdown banks. See LCO 3.1.4, "Rod Group Alignment Limits," for control and shutdown rod OPERABILITY and alignment requirements, and LCO 3.1.7, "Rod Position Indication," for position indication requirements.
The control banks are used for precise reactivity control of the reactor.
The positions of the control banks are normally automatically controlled by the Rod Control System, but they can also be manually controlled. They are capable of adding negative reactivity very quickly (compared to borating). The control banks must be maintained above designed insertion limits and are typically near the fully withdrawn position during
normal full power operations.
KewauneePower Station (KPS) has 4, the groups If 2 2 B 3.1.5 1 INSERT 1 USAR GDC 6, "Reactor Core Design," GDC 27, "Redundancy of Reactivity Control," GDC 28, "Reactivity Hot S hutdown Capability," GDC 29, "Reactivity Shutdown Capability," and GDC 30, "Reactivity Holddown Capability" (Ref. 1),
Insert Page B 3.1.5-1 o -
Shutdown Bank Insertion Limits B 3.1.5 WOG STS B 3.1.5-2 Rev. 3.0, 03/31/04 BASES BACKGROUND (continued)
Hence, they are not capable of adding a large amount of positive reactivity. Boration or dilution of the Reactor Coolant System (RCS) compensates for the reactivity changes associated with large changes in RCS temperature. The design calculations are performed with the assumption that the shutdown banks are withdrawn first. The shutdown banks can be fully withdrawn without the core going critical. This provides available negative reactivity in the event of boration errors. The shutdown banks are controlled manually by the control room operator.
During normal unit operation, the shutdown banks are either fully withdrawn or fully inserted. The shutdown banks must be completely withdrawn from the core, prior to withdrawing any control banks during an approach to criticality. The shutdown banks are then left in this position until the reactor is shut down. They affect core power and burnup distribution, and add negative reactivity to shut down the reactor upon receipt of a reactor trip signal.
1 APPLICABLE On a reactor trip, all RCCAs (s hutdown banks and contro l banks), except SAFETY the most reactive RCCA, are assumed to insert into the core. The ANALYSES shutdown banks shall be at or above their insertion limits and available to insert the maximum amount of negative reactivity on a reactor trip signal.
The control banks may be partially inserted in the core, as allowed by LCO 3.1.6, "Control Bank Insertion Limits." The shutdown bank and control bank insertion limits are established to ensure that a sufficient amount of negative reactivity is available to shut down the reactor and maintain the required SDM (see LCO 3.1.1, "SHUTDOWN MARGIN (SDM)") following a reactor trip from full power. The combination of control banks and shutdown banks (less the most reactive RCCA, which is assumed to be fully withdrawn) is sufficient to take the reactor from full power conditions at rated temperature to zero power, and to maintain the required SDM at rated no load temperature (Ref. 3). The shutdown bank insertion limit also limits the reactivity worth of an ejected shutdown rod.
The acceptance criteria for addressing shutdown and control rod bank insertion limits and inoperability or misalignment is that:
- a. There be no violations of:
- 1. Specified acceptable fuel design limits or 3 2. RCS pressure boundary integrity and
- 3; Shutdown Bank Insertion Limits B 3.1.5 WOG STS B 3.1.5-3 Rev. 3.0, 03/31/04 BASES APPLICABLE SAFETY ANALYSES (continued)
- b. The core remains subcritical after accident transients.
As such, the shutdown bank insertion limits affect safety analysis
involving core reactivity and SDM (Ref. 3).
The shutdown bank insertion limits preserve an initial condition assumed in the safety analyses and, as such, satisfy Criterion 2 of 10 CFR 50.36(c)(2)(ii).
LCO The shutdown banks must be within their insertion limits any time the reactor is critical or approaching criticality. This ensures that a sufficient amount of negative reactivity is available to shut down the reactor and maintain the required SDM following a reactor trip.
The shutdown bank insertion limits are defined in the COLR.
APPLICABILITY The shutdown banks must be within their insertion limits, with the reactor in MODES 1 and 2. This ensures that a sufficient amount of negative reactivity is available to shut down the reactor and maintain the required SDM following a reactor trip. The shutdown banks do not have to be within their insertion limits in MODE 3, unless an approach to criticality is being made. In MODE 3, 4, 5, or 6, the shutdown banks are fully inserted in the core and contribute to the SDM. Refer to LCO 3.1.1 for SDM requirements in MODES 3, 4, and 5. LCO 3.9.1, "Boron Concentration,"
ensures adequate SDM in MODE 6.
The Applicability requirements have been modified by a Note indicating the LCO requirement is suspended during SR 3.1.4.2. This SR verifies the freedom of the rods to move, and requires the shutdown bank to move below the LCO limits, which would normally violate the LCO.
ACTIONS A.1.1, A.1.2, and A.2 When one or more shutdown banks is not within insertion limits, 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is allowed to restore the shutdown banks to within the insertion limits.
This is necessary because the available SDM may be significantly reduced, with one or more of the shutdown banks not within their insertion limits. Also, verification of SDM or initiation of boration within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> is required, since the SDM in MODES 1 and 2 is ensured by adhering to the control and shutdown bank insertion limits (see LCO 3.1.1). If shutdown banks are not within their insertion limits, then SDM will be verified by performing a reactivity balance calculation, considering the effects listed in the BASES for SR 3.1.1.1.
5 Shutdown Bank Insertion Limits B 3.1.5 WOG STS B 3.1.5-4 Rev. 3.0, 03/31/04 BASES ACTIONS (continued)
The allowed Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> provides an acceptable time for evaluating and repairing minor problems without allowing the plant to remain in an unacceptable condition for an extended period of time.
B.1 If the shutdown banks cannot be restored to within their insertion limits within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, the unit must be brought to a MODE where the LCO is not applicable. The allowed Completion Time of 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> is reasonable, based on operating experience, for reaching the required MODE from full power conditions in an orderly manner and without challenging plant systems. any Required Action and associated Completion Time is not met 6 SURVEILLANCE SR 3.1.5.1 REQUIREMENTS Verification that the shutdown banks are within their insertion limits prior to an approach to criticality ensures that when the reactor is critical, or being taken critical, the shutdown banks will be available to shut down the reactor, and the required SDM will be maintained following a reactor trip.
This SR and Frequency ensure that the shutdown banks are withdrawn before the control banks are withdrawn during a unit startup.
Since the shutdown banks are positi oned manually by the control room operator, a verification of shutdown bank position at a Frequency of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, after the reactor is taken critical, is adequate to ensure that they are within their insertion limits. Also, the 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Frequency takes into account other information available in the control room for the purpose of monitoring the status of shutdown rods.
REFERENCES 1. 10 CFR 50, Appendix A, GDC 10, GDC 26, and GDC 28.
1USAR, Sections 3.1.2.1, 3.1.2.3, 3.1.2.4, 3.1.2.5, and 3.1.2.6.
- 2. 10 CFR 50.46.
- 3. FSAR, Chapter [15].
U Section 14.1 2
JUSTIFICATION FOR DEVIATIONS ITS 3.1.5 BASES, SHUTDOWN BANK INSERTION LIMITS
- 1. ISTS 3.1.5 Bases Background references General Design Criteria. Kewaunee Power Station (KPS) was designed prior to promulgation of 10 CFR 50, Appendix A. Therefore, ITS 3.1.5 Bases Background has been revised to discuss the design standards used by KPS. Additionally, Base s references to 10 CFR 50, Appendix A have been replaced with references to the appropriate section of the USAR.
- 2. Changes are made (additions, deletions, and/or changes) to the ISTS Bases which reflect the plant specific nomenclature, number, reference, system description, analysis, or licensing basis description.
- 3. The punctuation corrections have been made consistent with the Writer's Guide from the Improved Technical Specifications, TSTF-GG-05-01, Section 5.1.3.
- 4. Words changed to be consistent with similar words in the ISTS 3.1.4 Bases. Not all banks are divided into two groups at KPS.
- 5. Typographical error corrected.
- 6. Change made to be consistent with the Specification. The words in the ISTS Bases only describe Required Action A.2. ACTION B must be entered if any Required Action and associated Completion Time of Condition A is not met.
Kewaunee Power Station Page 1 of 1 Specific No Significant Haza rds Considerations (NSHCs)
DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATIONS ITS 3.1.5, SHUTDOWN BANK INSERTION LIMITS There are no specific NSHC discussions for this Specification.
Kewaunee Power Station Page 1 of 1 ATTACHMENT 6 ITS 3.1.6, CONTROL BANK INSERTION LIMITS Current Technical Specification (CTS) Markup and Discussion of Changes (DOCs)
A01 ITS 3.1.6 ITS c. Quadrant Power Tilt Limits
- 1. Except for physics tests, whenever the indicated quadrant power tilt ratio > 1.02, one of the following actions shall be taken within two hours:
A. Eliminate the tilt.
B. Restrict maximum core power level 2% for every 1% of indicated power tilt ratio
> 1.0. 2. If the tilt condition is not eliminated after 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, then reduce power to 50% or lower.
- 3. Except for Low Power Physics Tests, if the indicated quadrant tilt is > 1.09 and there is simultaneous indication of a misaligned rod:
A. Restrict maximum core power level by 2% of rated values for every 1% of indicated power tilt ratio > 1.0.
B. If the tilt condition is not eliminated within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, then the reactor shall be brought to a minimum load condition (30 Mwe). 4. If the indicated quadrant tilt is > 1.09 and there is no simultaneous indication of rod misalignment, then the reactor shall immediately be brought to a no load condition
( 5% reactor power).
- d. Rod Insertion Limits
- 1. The shutdown rods shall be withdrawn to within the limits, specified in the COLR, when the reactor is critical or approaching criticality.
- 2. The control banks shall be limited in physical insertion; insertion limits are specified in the COLR. If any one of the control bank insertion limits is not met:
A. Within one hour, initiate boration to restore control bank insertion to within the limits specified in the COLR, and B. Restore control bank insertion to within the limits specified in the COLR within two hours of exceeding the insertion limits. C. If any one of the conditions of TS 3.10.d.2.A or TS 3.10.d.2.B cannot be met, then withinone hour action shall be initiated to:
- Achieve HOT STANDBY within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />
- Achieve HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />
- 3. Insertion limit does not apply during physics tests or during periodic exercise of individual rods. However, the shutdown margin, as specified in the COLR, must be maintained except for the Low Power Physics Test to measure control rod worth and shutdown margin. For this test, the reactor may be critical with all but one high worth
rod inserted. See ITS 3.2.4 See ITS 3.1.8 A CTION A, A CTION B A CTION C L01See ITS 3.1.8 M01Add proposed SR 3.1.6.1, SR 3.1.6.2, and SR 3.1.6.3 Applicability Note See ITS 3.1.5 , sequence, and overlap limits Add proposed Required Actions A.1.1 and B.1.1 L02 L01Add proposed ApplicabilityA02 LCO 3.1.6 Amendment No. 165 TS 3.10-4 03/11/2003 Page 1 of 1 DISCUSSION OF CHANGES ITS 3.1.6, CONTROL BANK INSERTION LIMITS ADMINISTRATIVE CHANGES A01 In the conversion of the Kewaunee Power Station (KPS) Current Technical Specifications (CTS) to the plant specific Improved Technical Specifications (ITS), certain changes (wording preferences, editorial changes, reformatting, revised numbering, etc.) are made to obtain consistency with NUREG-1431, Rev. 3.0, "Standard Technical Specifications-Westinghouse Plants" (ISTS).
These changes are designated as administrative changes and are acceptable because they do not result in technical changes to the CTS.
A02 CTS 3.10.d.2 requires, in part, that the control rod banks are to be limited in physical insertion as specified in the COLR. ITS 3.1.6 requires the control bank to be within the insertion, sequence, and overlap limits specified in the COLR. This changes the CTS by specifically stating that the control bank physical insertion limits are the control bank insertion, overlap, and sequence limits.
This change is acceptable because the LCO requirements have not changed. COLR Section 2.5 states, in part, that physical insertion limits are shown in COLR Figure 4. COLR Figure 4 is a graphical presentation of when each control bank is required to be withdrawn with respect to the Percent of Rated Thermal Power. As shown in the Figure, the sequence of control bank withdrawal is included. Additionally, the Note for COLR Figure 4 states that the Rod Bank Insertion Limits are based on a control bank tip-to-tip distance of 126 steps.
Furthermore, the COLR Figure 4 is similar to the ISTS Bases Figure B 3.1.6.
Therefore, the physical insertion limits in CTS 3.10.d.2 include the insertion, sequence, and overlap limits. This change is designated as an administrative change since it does not result in any technical changes to the CTS.
MORE RESTRICTIVE CHANGES
M01 CTS 3.10.d does not provide any Surveillance Requirements for verifying control bank insertion limits. ITS SR 3.1.6.1 requires verifying that the estimated critical control bank position is within the insertion limits specified in the COLR within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> prior to achieving criticality. ITS SR 3.1.6.2 requires verifying that each control bank insertion is within the insertion limits specified in the COLR every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. ITS SR 3.1.6.3 requires verification that the overlap and sequence limits specified in the COLR are met for control banks not fully withdrawn from the core every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. This changes the CTS by adding specific Surveillance Requirements to periodically verify that control banks will be within insertion, sequence and overlap limits specified in the COLR.
The purpose of ITS SR 3.1.6.1 is to ensure that the reactor does not achieve criticality with the control banks below their insertion limits. The purpose of ITS SR 3.1.6.2 is to detect control banks that may be approaching the insertion limits. The purpose of ITS SR 3.1.6.3 is to verify that control bank sequence and overlap is within the requirements specified in the COLR. Therefore, this change is considered acceptable and is more restrictive because new Surveillance Requirements have been added to periodically verify the LCO limits are met.
Kewaunee Power Station Page 1 of 3 DISCUSSION OF CHANGES ITS 3.1.6, CONTROL BANK INSERTION LIMITS RELOCATED SPECIFICATIONS None
REMOVED DETAIL CHANGES
None
LESS RESTRICTIVE CHANGES
L01 (Category 2 - Relaxation of Applicability) CTS 3.10.d.2 requires the control banks to be limited in physical insertion as specified in the COLR, but does not specifically state an applicability. CTS 3.10.d.2.A, B, and C provide actions to be taken if the control banks insertion limits are not met. If the control bank insertion limits are not restored, then the unit must be placed in HOT STANDBY (equivalent to ITS MODE 2) within 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br /> and in HOT SHUTDOWN (equivalent to ITS MODE 3) within 13 hours1.50463e-4 days <br />0.00361 hours <br />2.149471e-5 weeks <br />4.9465e-6 months <br />. Thus, the effective Applicability for the control bank insertion limits is OPERATING and HOT STANDBY MODES (equivalent to ITS MODES 1 and 2). ITS 3.1.6 requires the control bank insertion limits to be met in MODE 1 and in MODE 2 with k eff 1.0. This changes the CTS by only requiring the control bank limits to met in MODE 2 with k eff 1.0, in lieu of at all times in MODE 2. Consistent with this change in Applicability, the requirements in CTS 3.10.d.2.C to be in HOT STANDBY and HOT SHUTDOWN are changed
to be in MODE 2 with k eff < 1.0 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
The control bank insertion limits are required to prevent core power distributions that could result in fuel cladding failures in the event of a LOCA, loss of flow, ejected rod, or other accident requiring termination by an RPS trip function. This change is acceptable because in MODE 2 with k eff < 1.0, neither the assumed power distribution nor the ejected rod worth would be exceeded. Furthermore, allowing 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> to be in MODE 2 with k eff < 1.0 is a reasonable time, based on operating experience, for reaching the required MODE from full power in an orderly manner and without challenging plant systems. This proposed ACTION also places the unit outside the new Applicability. This change is designated as less restrictive because the Applicability has been changed to MODE 1 and MODE 2 with k eff 1.0.
L02 (Category 4 - Relaxation of Required Action) CTS 3.10.d.2.A requires that if the control banks physical insertion limits (i.e., insertion, sequence, or overlap) are not met, then within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> initiate boration to restore control bank insertion to within limits. ITS 3.1.6 ACTION A and ACTION B contain the same requirements but allows a choice between verifying that the SDM is within the limits specified in the COLR (ITS 3.1.6 Required Actions A.1.1 and B.1.1) within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> or initiating boration to restore SDM to within limits within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> (ITS 3.1.6 Required Actions A.1.2 and B.1.2). This changes the CTS by allowing either the verification that SDM is within the limits specified in the COLR or the initiation of boration to restore the required SDM within one hour when the control banks are not within the physical insertion limits.
Kewaunee Power Station Page 2 of 3 DISCUSSION OF CHANGES ITS 3.1.6, CONTROL BANK INSERTION LIMITS Kewaunee Power Station Page 3 of 3 This change is acceptable because it requires verification that the initial conditions of the analysis is maintained. In MODE 1 and MODE 2 with k eff > 1.0, SDM is normally ensured by adhering to the control and shutdown bank insertion limits. If the control banks are not within their insertion limits, then SDM must be verified to be within limits or boration must be initiated to restore SDM to within limits. This change is designated as less restrictive because an alternate allowance to verify SDM is within the limits specified in the COLR is being added to the CTS.
Improved Standard Technical Specifications (ISTS) Markup and Justification for Deviations (JFDs)
Control Bank Insertion Limits 3.1.6 WOG STS 3.1.6-1 Rev. 3.0, 03/31/04 CTS 3.1 REACTIVITY CONTROL SYSTEMS
3.1.6 Control
Bank Insertion Limits
LCO 3.1.6 Control banks shall be within the insertion, sequence, and overlap limits specified in the COLR.
APPLICABILITY: MODE 1, MODE 2 with k eff 1.0. -------------------------------------------NOTE----------------------------------------------
This LCO is not applicable while performing SR 3.1.4.2.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME
A. Control bank insertion limits not met.
A.1.1 Verify SDM is within the limits specified in the COLR.
OR A.1.2 Initiate boration to restore SDM to within limit.
AND A.2 Restore control bank(s) to within limits.
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />
2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> B. Control bank sequence or overlap limits not met.
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 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> 3.10.d.3 3.10.d.2.A, 3.10.d.2.B s s 3.10.d.2.A, 3.10.d.2.B DOC L01 3.10.d.2 1 1 Control Bank Insertion Limits 3.1.6 WOG STS 3.1.6-2 Rev. 3.0, 03/31/04 CTS ACTIONS (continued)
CONDITION REQUIRED ACTION COMPLETION TIME
B.2 Restore control bank sequence and overlap to within limits.
2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> C. Required Action and associated Completion Time not met.
C.1 Be in MODE 2 with k eff < 1.0.
6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> 3.10.d.2.A, 3.10.d.2.B 3.10.d.2.C
SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY
SR 3.1.6.1 Verify estimated critical control bank position is within the limits specified in the COLR.
Within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> prior to achieving criticality
SR 3.1.6.2 Verify each control bank insertion is within the insertion limits specified in the COLR.
12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> SR 3.1.6.3 Verify sequence and overlap limits specified in the COLR are met for control banks not fully withdrawn
from the core.
12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> DOC M02 2insertion DOC M02 DOC M02 JUSTIFICATION FOR DEVIATIONS ITS 3.1.6, CONTROL BANK INSERTION LIMITS
- 1. Typographical/grammatical error corrected to be consistent with the wording in the proceeding Required Action.
- 2. SR 3.1.6.1 is clarified to state that the estimated critical control bank position must be verified to be within the "insertion limits," specified in the COLR. This Specification requires three limits to be met; insertion, sequence, and overlap. As stated in the ISTS SR 3.1.6.1 Bases, the limit to be checked is only the insertion limit.
Kewaunee Power Station Page 1 of 1 Improved Standard Technical Specifications (ISTS) Bases Markup and Bases Justification for Deviations (JFDs)
Control Bank Insertion Limits B 3.1.6 WOG STS B 3.1.6-1 Rev. 3.0, 03/31/04 B 3.1 REACTIVITY CONTROL SYSTEMS
B 3.1.6 Control Bank Insertion Limits
BASES BACKGROUND The insertion limits of the shutdown and control rods are initial assumptions in all safety analyses that assume rod insertion upon reactor trip. The insertion limits directly affect core power and fuel burnup distributions and assumptions of available SDM, and initial reactivity insertion rate.
The applicable criteria for these reactivity and power distribution design requirements are 10 CFR 50, Appendix A, GDC 10, "Reactor Design," GDC 26, "Reactivity Control System Redundancy and Protection," GDC 28, "Reactivity Limits" (Ref. 1), and 10 CFR 50.46, "Acceptance Criteria for Emergency Core Cooling Systems for Light Water Nuclear Power Reactors" (Ref. 2). Limits on control rod insertion 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. INSERT 1 1 The rod cluster control assemblies (RCCAs) are divided among control banks and shutdown banks. Each bank may be further subdivided into two groups to provide for precise reactivity control. A group consists of two or more RCCAs that are electrically paralleled to step simultaneously. A bank of RCCAs consists of two groups that are moved in a staggered fashion, but always within one step of each other. All plants have four control banks and at least two shutdown banks. See LCO 3.1.4, "Rod Group Alignment Limits," for control and shutdown rod OPERABILITY and alignment requirements, and LCO 3.1.7, "Rod Position Indication," for position indication requirements. If , the groups 6KewauneePower Station (KPS) has 2 3The control bank insertion limits are specified in the COLR. An example is provided for information only in Figure B 3.1.6-1. The control banks are required to be at or above the insertion limit lines.
4Figure B 3.1.6-1 also indicates how the control banks are moved in an overlap pattern. Overlap is the distance travelled together by two control banks. The predetermined position of control bank C, at which control bank D will begin to move with bank C on a withdrawal, will be at 118 steps for a fully withdrawn position of 231 steps. The fully withdrawn position is defined in the COLR. INSERT 2 3 B 3.1.6 1 INSERT 1 USAR GDC 6, "Reactor Core Design," GDC 27, "Redundancy of Reactivity Control," GDC 28, "Reactivity Hot S hutdown Capability," GDC 29, "Reactivity Shutdown Capability," and GDC 30, "Reactivity Holddown Capability" (Ref. 1),
4 INSERT 2 The control bank sequence and overlap limits are specified in the COLR.
Sequencing is the order in which the banks are moved.
Insert Page B 3.1.6-1 Control Bank Insertion Limits B 3.1.6 WOG STS B 3.1.6-2 Rev. 3.0, 03/31/04 BASES BACKGROUND (continued)
The control banks are used for precise reactivity control of the reactor. The positions of the control banks are normally controlled automatically by the Rod Control System, but can also be manually controlled. They are capable of adding reactivity very quickly (compared to borating or diluting).
The power density at any point in the core must be limited, so that the fuel design criteria are maintained. Together, LCO 3.1.4, LCO 3.1.5, "Shutdown Bank Insertion Limits," LCO 3.1.6, LCO 3.2.3, "AXIAL FLUX DIFFERENCE (AFD)," and LCO 3.2.4, "QUADRANT POWER TILT RATIO (QPTR)," provide limits on control component operation and on monitored process variables, which ensure that the core operates within the fuel design criteria.
The shutdown and control bank insertion and alignment limits, AFD, and QPTR are process variables that together characterize and control the three dimensional power distribution of the reactor core. Additionally, the control bank insertion limits control the reactivity that could be added in the event of a rod ejection accident, and the shutdown and control bank insertion limits ensure the required SDM is maintained.
Operation within the subject LCO limits will prevent fuel cladding failures that would breach the primary fission product barrier and release fission products to the reactor coolant in the event of a loss of coolant accident (LOCA), loss of flow, ejected rod, or other accident requiring termination by a Reactor Trip System (RTS) trip function.
APPLICABLE The shutdown and control bank insertion limits, AFD, and QPTR LCOs SAFETY are required to prevent power distributions that could result in fuel ANALYSES cladding failures in the event of a LOCA, loss of flow, ejected rod, or other accident requiring termination by an RTS trip function.
The acceptance criteria for addressing shutdown and control bank insertion limits and inoperability or misalignment are that:
- a. There be no violations of:
5 1. Specified acceptable fuel design limits or
- 2. Reactor Coolant System pressure boundary integrity and
- b. The core remains subcritical after accident transients.
As such, the shutdown and control bank insertion limits affect safety analysis involving core reactivity and power distributions (Ref. 3).
The SDM requirement is ensured by limiting the control and shutdown bank insertion limits so that allowable inserted worth of the RCCAs is such that sufficient reactivity is available in the rods to shut down the reactor to hot zero power with a reactivity margin that assumes the maximum worth RCCA remains fully withdrawn upon trip (Ref. 4).
Operation at the insertion limits or AFD limits may approach the maximum allowable linear heat generation rate or peaking factor with the allowed QPTR present. Operation at the insertion limit may also indicate the maximum ejected RCCA worth could be equal to the limiting value in fuel cycles that have sufficiently high ejected RCCA worths.
The control and shutdown bank insertion limits ensure that safety analyses assumptions for SDM, ejected rod worth, and power distribution peaking factors are preserved (Ref. 5).
The insertion limits satisfy Criterion 2 of 10 CFR 50.36(c)(2)(ii), in that they are initial conditions assumed in the safety analysis.
control bank 2 LCO The limits on control banks sequence, overlap, and physical insertion, as defined in the COLR, must be maintained because they serve the function of preserving power distribution, ensuring that the SDM is maintained, ensuring that ejected rod worth is maintained, and ensuring adequate negative reactivity insertion is available on trip. The overlap between control banks provides more uniform rates of reactivity insertion and withdrawal and is imposed to maintain acceptable power peaking during control bank motion.
APPLICABILITY The control bank sequence, overl ap, and physical insertion limits shall be maintained with the reactor in MODES 1 and 2 with k eff 1.0. These limits must be maintained, since they preserve the assumed power distribution, ejected rod worth, SDM, and reactivity rate insertion assumptions. Applicability in MODES 3, 4, and 5 is not required, since neither the power distribution nor ejected rod worth assumptions would be
exceeded in these MODES. in MODE 2 with k eff < 1.0 and 2 The applicability requirements have been modified by a Note indicating the LCO requirements are suspended during the performance of SR 3.1.4.2. This SR verifies the freedom of the rods to move, and requires the control bank to move below the LCO limits, which would violate the LCO.
Control Bank Insertion Limits B 3.1.6 WOG STS B 3.1.6-4 Rev. 3.0, 03/31/04 BASES ACTIONS A.1.1, A.1.2, A.2, B.1.1, B.1.2, and B.2 When the control banks are outside the acceptable insertion limits, they must be restored to within those limits. This restoration can occur in two ways: 5 a. Reducing power to be consistent with rod position or
- b. Moving rods to be consistent with power.
Also, verification of SDM or initiation of boration to regain SDM is required within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, since the SDM in MODES 1 and 2 normally ensured by adhering to the control and shutdown bank insertion limits (see LCO 3.1.1, "SHUTDOWN MARGIN (SDM)") has been upset. If control banks are not within their insertion limits, then SDM will be verified by performing a reactivity balance calculation, considering the effects listed in the BASES for SR 3.1.1.1.
7 Similarly, if the control banks are found to be out of sequence or in the wrong overlap configuration, they must be restored to meet the limits.
Operation beyond the LCO limits is allowed for a short time period in order to take conservative action because the simultaneous occurrence of either a LOCA, loss of flow accident, ejected rod accident, or other accident during this short time period, together with an inadequate power distribution or reactivity capability, has an acceptably low probability.
The allowed Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for restoring the banks to within the insertion, sequence, and overlaps limits provides an acceptable time for evaluating and repairing minor problems without allowing the plant to remain in an unacceptable condition for an extended period of time.
7 any Required Action and associated Completion Time is not met C.1 8If Required Actions A.1 and A.2, or B.1 and B.2 cannot be completed within the associated Completion Times, the plant must be brought to MODE 2 with k eff < 1.0, where the LCO is not applicable. The allowed Completion Time of 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> is reasonable, based on operating experience, for reaching the required MODE from full power conditions in an orderly manner and without challenging plant systems.
Control Bank Insertion Limits B 3.1.6 WOG STS B 3.1.6-5 Rev. 3.0, 03/31/04 BASES SURVEILLANCE SR 3.1.6.1 REQUIREMENTS This Surveillance is required to ensure that the reactor does not achieve criticality with the control banks below their insertion limits.
The estimated critical position (ECP) depends upon a number of factors, one of which is xenon concentration. If the ECP was calculated long before criticality, xenon concentration could change to make the ECP substantially in error. Conversely, determining the ECP immediately before criticality could be an unnecessary burden. There are a number of unit parameters requiring operator attention at that point. Performing the ECP calculation within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> prior to criticality avoids a large error from changes in xenon concentration, but allows the operator some flexibility to schedule the ECP calculation with other startup activities.
Verification of the control bank insertion limits at a Frequency of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> is sufficient to detect control banks that may be approaching the insertion limits since, normally, very little rod motion occurs in 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
When control banks are maintained within their insertion limits as checked by SR 3.1.6.2 above, it is unlikely that their sequence and overlap will not be in accordance with requirements provided in the COLR. A Frequency of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> is consistent with the insertion limit check above in SR 3.1.6.2.
REFERENCES 1. 10 CFR 50, Appendix A, GDC 10, GDC 26, GDC 28.
1
- 2. 10 CFR 50.46.
- 3. FSAR, Chapter [15]. USAR, Sections 3.1.2.1, 3.1.2.3, 3.1.2.4, 3.1.2.5, and 3.1.2.6. Section 14.1 U 2 4. FSAR, Chapter [15].
- 5. FSAR, Chapter [15].
2 Control Bank Insertion Limits B 3.1.6 WOG STS B 3.1.6-6 Rev. 3.0, 03/31/04 Figure B 3.1.6 (page 1 of 1) Control Bank Insertion vs. Percent RTP 3 231 200 ...---U) :z: 150 o I-en o a... 100 co ---.J o a: :z: o C> o o (17,231) (0,191 ) (100,190) 60 THIS FIGURE FOR ILLUSTRATION ONLY. DO NOT USE FOR OPERATION.
PERCENT OF RTP 100 JUSTIFICATION FOR DEVIATIONS ITS 3.1.6 BASES, CONTROL BANK INSERTION LIMITS
- 1. ISTS 3.1.6 Bases Background references General Design Criteria. Kewaunee Power Station (KPS) was designed prior to promulgation of 10 CFR 50, Appendix A. Therefore, ITS 3.1.6 Bases Background has been revised to discuss the design standards used by KPS. Additionally, Base s references to 10 CFR 50, Appendix A have been replaced with references to the appropriate section of the USAR.
- 2. Changes are made (additions, deletions, and/or changes) to the ISTS Bases which reflect the plant specific nomenclature, number, reference, system description, analysis, or licensing basis description.
- 3. Since the ITS states the actual control bank insertion, sequence, and overlap limits are specified in the COLR, the example provided for information only is not needed in the Bases and has been deleted. Furthermore, since the overlap limits are specified in the COLR, the description of the actual value of the limit provided in the paragraph is also not needed and has been deleted.
- 4. LCO 3.1.6 governs control bank insertion, sequence, and overlap limits. The Background section of ITS 3.1.6 Bases discusses insertion and overlaps, but does not discuss sequence. A discussion of control bank sequence is added for completeness.
- 5. The punctuation corrections have been made consistent with the Writer's Guide from the Improved Technical Specifications, TSTF-GG-05-01, Section 5.1.3.
- 6. The wording has been changed to be consistent with the wording used in Bases of ISTS 3.1.4.
- 7. Typographical/grammatical error corrected.
- 8. Change made to be consistent with the Specification. The words in the ISTS Bases implies that Condition C is entered only when both Required Actions A.1 and A.2, or both Required Actions B.1 and B.2 are not met. Condition C is to be entered if any Required Action of ACTION A or B is not met. In addition, there is no Required Action A.1 or B.1.
Kewaunee Power Station Page 1 of 1 Specific No Significant Haza rds Considerations (NSHCs)
DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATIONS ITS 3.1.6, CONTROL BANK INSERTION LIMITS There are no specific NSHC discussions for this Specification.
Kewaunee Power Station Page 1 of 1 ATTACHMENT 7 ITS 3.1.7, ROD POSITION INDICATION Current Technical Specification (CTS) Markup and Discussion of Changes (DOCs)
ITS 3.1.7A01ITS e. Rod Misalignment Limitations NOTE: Individual RPIs may be outside their limits for
< 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> following substantial rod movement This specification defines allowable limits for misaligned rod cluster control assemblies. In TS 3.10.e.1 and TS 3.10.e.2, the magnitude, in steps, of an indicated rod misalignment may be determined by comparison of the respective bank demand step counter to the analog individual rod position indicator, the rod position as noted on the plant process computer, or through the conditioning module output voltage via a correlation of rod position vs. voltage.
Rod misalignment limitations do not apply during physics testing.
See ITS 3.1.8 See ITS 3.1.4 1. When reactor power is 85% of rating, the rod cluster control assembly shall be maintained within +/- 12 steps from their respective banks. If a rod cluster control assembly is misaligned from its bank by more than +/- 12 steps when reactor power is 85%, then the rod will be realigned or the core power peaking factors shall be determined within four hours, and TS 3.10.b applied. If peaking factors are not determined within four hours, the reactor power shall be reduced to < 85% of rating. 2. When reactor power is < 85% but 50% of rating, the rod cluster control assemblies shall be maintained within +/- 24 steps from their respective banks. If a rod cluster control assembly is misaligned from its bank by more than +/- 24 steps when reactor power is
< 85% but 50%, the rod will be realigned or the core power peaking factors shall be determined within four hours, and TS 3.10.b applied. If the peaking factors are not determined within four hours, the reactor power shall be reduced to < 50% of rating. 3. And, in addition to TS 3.10.e.1 and TS 3.10.e.2, if the misaligned rod cluster control assembly is not realigned within eight hours, the rod shall be declared inoperable.
See ITS 3.1.4 f. Inoperable Rod Position Indicator Channels Add proposed ApplicabilityA02Add proposed LCO statement NOTE: Individual RPIs may be outside their limits for
< 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> following substantial rod movement See ITS 3.1.4 1. If one individual rod position indicator channel per group is inoperable for one or more groups, then perform either A or B below: (Note: Separate entry condition is allowed for
each inoperable individual rod position indicator.)
A CTIONS Note A CTION A A. Verify the position of the rod cluster control indirectly by movable incore detectors each eight hours, or B. Within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> reduce reactor thermal power to 50% of RATED POWER. A CTION A 2. If more than one individual rod position indicator channel per group are inoperable, then:
A. IMMEDIATELY place the control rods in manual, and B. Once per 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, monitor and record RCS Tavg , and A CTION B C. Verify the position of the rod by movable incore detectors each 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, and A CTION A Amendment No. 181 TS 3.10-5 03/24/2005 Page 1 of 4 ITS 3.1.7A01ITS D. Within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> restore the inoperable individual rod position indicators to OPERABLE status such that a maximum of one IRPI per group is inoperable or place the plant in HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
such that a maximum of one IRPI per group is inoperable or place the plant in HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
A CTION B A CTION D 3. If one or more rods with inoperable individual rod position indicators have been moved in excess of 24 steps in one direction since the last determination of the rods position
then perform A or B below: 3. If one or more rods with inoperable individual rod position indicators have been moved in excess of 24 steps in one direction since the last determination of the rods position
then perform A or B below: A. Within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> verify the position of the rod by movable incore detectors, or A. Within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> verify the position of the rod by movable incore detectors, or B. Within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> reduce reactor thermal power to 50% of RATED POWER. B. Within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> reduce reactor thermal power to 50% of RATED POWER.
A CTION A 4. If one demand position indicator per bank for one or more banks is inoperable then perform either A or B below: (Note: Separate condition entry is allowed for each inoperable demand position indicator.) 4. If one demand position indicator per bank for one or more banks is inoperable then perform either A or B below: (Note: Separate condition entry is allowed for each
inoperable demand position indicator.)
A CTIONS Note A CTION C A. Each 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> verify, A. Each 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> verify, 1) All IRPI's for the affected banks are OPERABLE, by administrative means, and 1) All IRPI's for the affected banks are OPERABLE, by administrative means, and 2) The most withdrawn rod and the least withdrawn rod of the affected bank(s) are 12 steps apart when > 85% RATED POWER or 24 steps when 85% RATED POWER. 2) The most withdrawn rod and the least withdrawn rod of the affected bank(s) are 12 steps apart when > 85% RATED POWER or 24 steps when 85% RATED POWER.
B. Within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, reduce reactor thermal power to 50% of RATED POWER. B. Within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, reduce reactor thermal power to 50% of RATED POWER.
A CTION C A03 5. If a rod cluster control assembly having a rod position indicator channel out of service is found to be misaligned from TS 3.10.f.1.A, then TS 3.10.e will be applied. 5. If a rod cluster control assembly having a rod position indicator channel out of service is found to be misaligned from TS 3.10.f.1.A, then TS 3.10.e will be applied. A04 Amendment No. 181 TS 3.10-6 03/24/2005 Page 2 of 4 ITS 3.1.7 A01ITS 4.1 OPERATIONAL SAFETY REVIEW APPLICABILITY Applies to items directly related to safety limits and LIMITING CONDITIONS FOR OPERATION.
OBJECTIVE To assure that instrumentation shall be checked, tested, and calibrated, and that equipment and sampling tests shall be conducted at sufficiently frequent intervals to
ensure safe operation.
SPECIFICATION
- a. Calibration, testing, and checking of protective instrumentation channels and testing of logic channels shall be performed as specified in Table TS 4.1-1.
- b. Equipment and sampling tests shall be conducted as specified in Table TS 4.1-2 and TS 4.1-3.
- c. Deleted
- d. Deleted
- e. Deleted See other ITS Amendment No. 119 TS 4.1-1 04/18/95 Page 3 of 4 TABLE TS 4.1-1 MINIMUM FREQUENCIES FOR CHECKS, CALIBRATIONS AND TEST OF INSTRUMENT CHANNELS Amendment No. 151 Page 2 of 7 02/12/2001 CHANNEL DESCRIPTION CHECK CALIBRATE TEST REMARKS 6. Pressurizer Water Level Each shift Each refueling cycle Monthly 7. Pressurizer Pressure Each shift Each refueling cycle Monthly 8. a. 4-KV Voltage and Frequency Not applicable Each refueling cycle Monthly Reactor protection circuits only b. 4-KV Voltage (Loss of Voltage)
Not applicable Each refueling cycle Monthly Safeguards buses only c. 4-KV Voltage (Degraded Grid)
Not applicable Each refueling cycle Monthly Safeguards buses only 9. Analog Rod Position Each shift(a,b)
Each refueling cycle Each refueling cycle (a) With step counters (b) Following rod motion in excess of 24 steps when computer is out of service 10. Rod Position Bank Counters Each shift(a,b)
Not applicable Each refueling cycle (a) With analog rod position (b) Following rod motion in excess of 24 steps when computer is out of service SR 3.1.7.1 See ITS 3.3.5 See ITS 3.3.1 and 3.3.2 See ITS 3.1.4 See ITS 3.1.4 SR 3.1.7.2 ITS A01 ITS 3.1.7 Page 4 of 4 DISCUSSION OF CHANGES ITS 3.1.7, ROD POSITION INDICATION ADMINISTRATIVE CHANGES A01 In the conversion of the Kewaunee Power Station (KPS) Current Technical Specifications (CTS) to the plant specific Improved Technical Specifications (ITS), certain changes (wording preferences, editorial changes, reformatting, revised numbering, etc.) are made to obtain consistency with NUREG-1431, Rev. 3.0, "Standard Technical Specifications-Westinghouse Plants" (ISTS).
These changes are designated as administrative changes and are acceptable because they do not result in technical changes to the CTS.
A02 CTS 3.10.f describes the ACTIONS to take for one inoperable individual rod position indicator channel per group, more than one inoperable individual rod position indicator channel per group, one or more rods with inoperable individual rod position indicators, and one demand position indicator bank inoperable for one or more banks. The lowest plant condition required by the CTS Actions (CTS 3.10.f.2.D) is HOT SHUTDOWN (ITS equivalent MODE 3). ITS 3.1.7 requires similar ACTIONS, but specifically states in the LCO that the Individual Rod Position Indication (IRPI) System and the Demand Position Indication System shall be OPERABLE in MODES 1 and 2. This changes the CTS by stating the specific Limiting Conditions for Operability (LCO) and the specific
MODE of Applicability.
This change is acceptable because the requirements for the IRPI System and the Demand Position Indication System have not changed. Actions will continue to be taken when the individual rod position indicators and the demand position indicator banks are inoperable. This change clearly states what is required to be OPERABLE and the MODE in which the Systems are required to be OPERABLE. Since the lowest plant condition required by the CTS Actions is HOT SHUTDOWN and the ITS Applicability is MODES 1 and 2. The proposed Applicability change is acceptable. This change is considered administrative because the technical requirements have not changed.
A03 CTS 3.10.f.4 provides the Actions if one demand position indicator per bank for one or more banks is inoperable. CTS 3.10.f.4.A.2) requires a verification that the most withdrawn rod and the least withdrawn rod of the affected bank(s) are
< 12 steps apart when > 85% RATED POWER or < 24 steps apart when <
85% RATED POWER. Under similar conditions, ITS 3.1.7 Required Action C.1.2 requires a verification that the most withdrawn rod and the least withdrawn rod of the affected bank are within the required rod alignment limits of LCO 3.1.4, "Rod Group Alignment Limits." This changes the CTS by not specifying the actual rod alignment limits in this Action, but referencing the applicable LCO where the limits are controlled.
The purpose of this CTS Action is to ensure the rod alignment limits are maintained when a demand position indicator is inoperable. This change is acceptable since the actual limits are not changing. ITS LCO 3.1.4 includes the appropriate limits, and ITS 3.1.4 Required Action C.1.2 references the appropriate LCO that controls the limits. This change is administrative since the technical requirements are not being changed.
Kewaunee Power Station Page 1 of 2 DISCUSSION OF CHANGES ITS 3.1.7, ROD POSITION INDICATION Kewaunee Power Station Page 2 of 2 A04 CTS 3.10.f.5 states that if a rod cluster control assembly having a rod position indicator channel out of service is found to be misaligned when performing 3.10.f.1.A, then 3.10.e will be applied. ITS 3.1.7 does not contain the statement.
This changes the CTS by not including the statement that if a rod cluster control assembly having a rod position indicator channel out of service is found to be misaligned, then 3.10.e will be applied.
This change is acceptable because CTS 3.10.f.5 is used to alert the user that a misaligned rod cluster control assembly is covered under a separate LCO requirement. It is an ITS convention to not include these types of cross references. ITS 3.1.4 provides the proper requirements for when a rod is misaligned, and a specific cross reference is not required. This change is designated as administrative as it incorporates an ITS convention with no technical change.
MORE RESTRICTIVE CHANGES None
RELOCATED SPECIFICATIONS
None
REMOVED DETAIL CHANGES
None
LESS RESTRICTIVE CHANGES None Improved Standard Technical Specifications (ISTS) Markup and Justification for Deviations (JFDs)
Rod Position Indication 3.1.7 WOG STS 3.1.7-1 Rev. 3.0, 03/31/04 CTS 3.1 REACTIVITY CONTROL SYSTEMS
3.1.7 Rod Position Indication
LCO 3.1.7 The [Digital] Rod Position Indication ([D]RPI) System and the Demand Position Indication System shall be OPERABLE. Individual I 1 DOC A 02 APPLICABILITY: MODES 1 and 2.
DOC A 02 ACTIONS
NOTE----------------------------------------------------------- Separate Condition entry is allowed for each inoperable rod position indicator and each demand position indicator.
CONDITION REQUIRED ACTION COMPLETION TIME A. One [D]RPI per group inoperable for one or more groups.
A.1 Verify the position of the rods with inoperable position indicators indirectly
by using movable incore detectors.
OR A.2 Reduce THERMAL POWER to 50% RTP.
Once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />
8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> B. More than one [D]RPI per group inoperable.
B.1 Place the control rods under manual control.
AND B.2 Monitor and record Reactor Coolant System Tavg.
AND Immediately
Once per 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> an INSERT 1 I I 3.10.f.2 3.10.f.1, 3.10.f.2.c 3.10.f.1, 3.10.f.4 1 4 2 3 1 3.1.7 3 INSERT 1 AND 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after a rod with an inoperable position indicator has been moved in excess of 24 steps in one direction since the last determination of the rod's position
Insert Page 3.1.7-1 Rod Position Indication 3.1.7 WOG STS 3.1.7-2 Rev. 3.0, 03/31/04 CTS ACTIONS (continued)
CONDITION REQUIRED ACTION COMPLETION TIME
B.3 Verify the position of the rods with inoperable position indicators indirectly by using the movable incore detectors.
AND B.4 Restore inoperable position indicators to OPERABLE status such that a maximum of one [D]RPI per group is inoperable.
Once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />
24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> C. One or more rods with inoperable position indicators have been moved in excess of 24 steps in one direction since the last determination of the rod's position.
C.1 Verify the position of the rods with inoperable position indicators indirectly
by using movable incore detectors.
OR C.2 Reduce THERMAL POWER to 50% RTP.
[4] hours
8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> D. One demand position indicator per bank inoperable for one or more banks.
D.1.1 Verify by administrative means all [D]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 Once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />
Once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> within the required rod alignment limits of LCO 3.1.4, "Rod Group Alignment Limits." I I C C 3 C 3.10.f.4 3.10.f.2 3 3 1 3 3 2 1 3 2 4 Rod Position Indication 3.1.7 WOG STS 3.1.7-3 Rev. 3.0, 03/31/04 CTS ACTIONS (continued)
CONDITION REQUIRED ACTION COMPLETION TIME
D.2 Reduce THERMAL POWER to 50% RTP.
8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> E. Required Action and associated Completion Time not met.
E.1 Be in MODE 3.
6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> 3.10.f.4 3 C 3 D 3.10.f.2.d D
SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY
SR 3.1.7.1 Verify each [D]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
Perform CHANNEL CALIBRATION of each IRPI.
18 months INSERT 2 5 Table 4.1-1 Item 9 3.1.7 CTS 5 INSERT 2 SR 3.1.7.2 Perform system functional test of the Demand Position Indication System.
18 months Table TS 4.1-1 Item 10 Insert Page 3.1.7-3 0_
JUSTIFICATION FOR DEVIATIONS ITS 3.1.7, ROD POSITION INDICATION
- 1. The ISTS contains bracketed information and/or values that are generic to all Westinghouse vintage plants. The brackets are removed and the proper plant specific information/value is provided. This is acceptable since the generic specific information/value is revised to reflect the current plant design.
- 2. The words in ISTS 3.1.7 Required Action A.1, ISTS 3.1.7 Required Action D.1.1 (ITS 3.1.7 Required Action C.1.1), and ISTS 3.1.7 Required Action D.1.2 (ITS
3.1.7 Required
Action C.1.2) have been modified to be singular, versus plural, when referring to a rod or a bank. This has been done since the ISTS 3.1.7 ACTIONS Note allows separate Condition entry for each rod position indicator and each demand position indicator; thus the Required Action only applies to the individual rod or bank whose indicator in inoperable. Furthermore, this change was approved during the DC Cook ITS conversion.
- 3. ISTS 3.1.7 ACTION C has two Required Actions that are connected with an OR. However, the stated Completion Time for these two Required Actions are different (4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> and 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, respectively). Due to the convention in the ISTS, as described in Section 1.3, the two Completion Times associated with the two
Required Actions OR logical connector must be the same, since either Required Action can be chosen. Therefore, to be consistent with the format of the ISTS, ISTS 3.1.7 ACTION C has been deleted and a new, conditional Completion Time has been added to Required Action A.1. This ensures that the intent of the ISTS is maintained, in that a verification of the position of the rod with an inoperable position indicator has been moved in excess of 24 steps in one direction since the last determination of the rod's position. In addition, since the unit is in both Conditions A and B when more than one rod position indicators per group are inoperable, and Required Action A.1 requires the identical position check required by Required Action B.3, there is no reason to include the position check as Required Action B.3. This is also consistent with the format of ISTS.
Furthermore, this change was approved for the DC Cook ITS conversion.
Appropriate renumbering changes have also been made due to these deletions.
- 4. ISTS Required Action D.1.2 has been revised to be consistent with the current KPS licensing basis requirements. The CTS allows a different alignment criterion
for 85% RATED POWER than it does for > 85% RATED POWER. Therefore, ITS 3.1.7 Required Action C.1.2 has been changed to met the alignment criteria specified in CTS 3.10.e (ITS 3.1.4).
- 5. The ISTS SR 3.1.7.1 requirement to verify each [D]RPI agrees within [12] steps of the group demand position for the full indicated range of rod travel prior to criticality after each removal of the reactor vessel head has been replaced by two new Surveillance Requirements. The first Surveillance is ITS SR 3.1.7.1 which requires performance of a CHANNEL CALIBRATION of each IRPI every 18 months. This Surveillance is acceptable because of the thermal drift characteristics of the IRPIs, performing a full range comparison of IRPI and demand position before criticality is not useful, as the IRPI response will change with IRPI temperature. The second Surveillance is ITS SR 3.1.7.2 which requires performance of a system functional test of the Demand Position Indication System (equivalent to CTS Rod Position Bank Counters) every 18 months. The performance of the CHANNEL CALIBRATION on the IRPIs and the system Kewaunee Power Station Page 1 of 2 JUSTIFICATION FOR DEVIATIONS ITS 3.1.7, ROD POSITION INDICATION Kewaunee Power Station Page 2 of 2 functional test of the Demand Position Indication System will align the ITS with the current licensing bases for Kewaunee Power Station.
Improved Standard Technical Specifications (ISTS) Bases Markup and Bases Justification for Deviations (JFDs)
Rod Position Indication B 3.1.7 WOG STS B 3.1.7-1 Rev. 3.0, 03/31/04 B 3.1 REACTIVITY CONTROL SYSTEMS
B 3.1.7 Rod Position Indication
BASES USAR, Section
7.1 BACKGROUND
According to GDC 13 (Ref. 1), instrumentation to monitor variables and systems over their operating ranges during normal operation, anticipated operational occurrences, and accident conditions must be OPERABLE. LCO 3.1.7 is required to ensure OPERABILITY of the control rod position indicators to determine control rod positions and thereby ensure compliance with the control rod alignment and insertion limits. INSERT 1 1 6 The OPERABILITY, including position indication, 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. Rod position indication is required to assess OPERABILITY and misalignment.
Mechanical or electrical failures may cause a control rod to become inoperable or to become misaligned from its group. Control 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 and OPERABILITY 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 out of the core (up or withdrawn) or into the core (down or inserted) by their control rod drive mechanisms. 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.
The axial position of shutdown rods and control rods are determined by two separate and independent systems: the Bank Demand Position Indication System (commonly called group step counters) and the [Digital] Rod Position Indication ([D]RPI) System.
3Individual I
B 3.1.7 1 INSERT 1 instrumentation and controls shall be provided as required to monitor and maintain within prescribed operating ranges essential reactor operating variables.
Insert Page B 3.1.7-1 o -
Rod Position Indication B 3.1.7 WOG STS B 3.1.7-2 Rev. 3.0, 03/31/04 BASES BACKGROUND (continued)
The Bank Demand Position Indication System counts the pulses from the Rod Control System that move 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 +/-
e 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. INSERT 1A 2 The [D]RPI System provides a highly 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 6 steps. To increase the reliability of the system, the inductive coils are connected alternately to data system A or B. Thus, if one system fails, the [D]RPI will go on half accuracy with an effective coil spacing of 7.5 inches, which is 12 steps. Therefore, the normal indication accuracy of the [D]RPI System is +/- 6 steps (+/- 3.75 inches), and the maximum uncertainty is +/- 12 steps (+/- 7.5 inches). With an indicated deviation of 12 steps between the group step counter and [D]RPI, the maximum deviation between actual rod position and the demand position could be 24 steps, or 15 inches.
APPLICABLE Control and shutdown rod positi on accuracy is essential during power SAFETY operation. Power peaking, ejected rod worth, or SDM limits may be ANALYSES violated in the event of a Design Basis Accident (Ref. 2), with control or shutdown rods operating outside their limits undetected. Therefore, the acceptance criteria for rod position indication is that rod positions must be known with sufficient accuracy in order to verify the core is operating within the group sequence, overlap, design peaking limits, ejected rod worth, and with minimum SDM (LCO 3.1.5, "Shutdown Bank Insertion Limits," and LCO 3.1.6, "Control Bank Insertion Limits"). The rod positions must also be known in order to verify the alignment limits are preserved (LCO 3.1.4, "Rod Group Alignment Limits"). Control rod positions are continuously monitored to provide operators with information that ensures the plant is operating within the bounds of the accident
analysis assumptions.
The control rod position indicator channels satisfy Criterion 2 of 10 CFR 50.36(c)(2)(ii). The control rod position indicators monitor control rod position, which is an initial condition of the accident. INSERT 2 2 2 I ion ies 3 2 6 I up to 24 36 5 5 5/8 8 B 3.1.7 2INSERT 1A The readout of the Bank Demand Position Indication System is in the form of an add and subtract counter reading. There is only one display for each rod group.
2 INSERT 2
an analog signal that is proportional to the actual control rod position. This is accomplished by using an electrical coil stack linear variable differential
transformer placed above the stepping mec hanism of the control rod magnetic jacks which are external to the pressure housing. When the control rod is at the bottom of the core, the magnetic coupling between the primary and secondary windings is small which induces a small voltage in the secondary. As the control rod raises, the lift rod causes an increase in magnetic coupling which in turn provides an analog signal proportional to the control rod position. The individual rod position indicator channels are sufficiently accurate to detect a rod + 12 steps away from its demand position.
Insert Page B 3.1.7-2 Rod Position Indication B 3.1.7 WOG STS B 3.1.7-3 Rev. 3.0, 03/31/04 BASES LCO LCO 3.1.7 specifies that one [D]RPI System and one Bank Demand Position Indication System be OPERABLE for each control rod. For the control rod position indicators to be OPERABLE requires meeting the SR of the LCO and the following:
the I 3 6 6 a. The [D]RPI System indicates within 12 steps of the group step counter demand position as required by LCO 3.1.4, "Rod Group
Alignment Limits," 7
- b. For the [D]RPI System there are no failed coils, and I 2 3 4
- c. The Bank Demand Indication System has been calibrated either in the fully inserted position or to the [D]RPI System.
b a ; 3 I The 12 step agreement limit between the Bank Demand Position Indication System and the [D]RPI System indicates that the Bank Demand Position Indication System is adequately calibrated, and can be used for indication of the measurement of control rod bank position.
A deviation of less than the allowable limit, given in LCO 3.1.4, in position indication for a single control rod, ensures high confidence that the position uncertainty of the corresponding control rod group is within the assumed values used in the analysis (that specified control rod group
insertion limits).
7 6These requirements ensure that control rod position indication during power operation and PHYSICS TESTS is accurate, and that design assumptions are not challenged.
OPERABILITY of the position indicator channels ensures that inoperable, misaligned, or mispositioned control rods can be detected. Therefore, power peaking, ejected rod worth, and SDM can be controlled within
acceptable limits.
rod 6 APPLICABILITY The requirements on the [D]RPI and step counters are only applicable in MODES 1 and 2 (consistent with LCO 3.1.4, LCO 3.1.5, and LCO 3.1.6),
because these are the only MODES in which power is generated, and the OPERABILITY and alignment of rods have the potential to affect the safety of the plant. In the shutdown MODES, the OPERABILITY of the shutdown and control banks has the potential to affect the required SDM, but this effect can be compensated for by an increase in the boron concentration of the Reactor Coolant System.
I 3 Rod Position Indication B 3.1.7 WOG STS B 3.1.7-4 Rev. 3.0, 03/31/04 BASES ACTIONS The ACTIONS Table is modified by a Note indicating that a separate Condition entry is allowed for each inoperable rod position indicator and each demand position indicator. This is acceptable because the Required Actions for each Condition provide appropriate compensatory actions for each inoperable position indicator.
A.1 When one [D]RPI channel per group fails, the position of the rod may still be determined indirectly by use of the movable incore detectors. The Required Action may also be satisfied by ensuring at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> that F Q satisfies LCO 3.2.1, satisfies LCO 3.2.2, and SHUTDOWN MARGIN is within the limits provided in the COLR, provided the nonindicating rods have not been moved. Based on experience, normal power operation does not require excessive movement of banks.
If a bank has been significantly moved, the Required Action of C.1 or C.2 below is required. Therefore, verification of RCCA position within the Completion Time of 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> is adequate for allowing continued full power operation, since the probability of simultaneously having a rod significantly out of position and an event sensitive to that rod position is
small. H N Fin a I 6 3 5 5 INSERT 3 A.2 Reduction of THERMAL POWER to 50% RTP puts the core into a condition where rod position is not significantly affecting core peaking factors (Ref. 3).
2 The allowed Completion Time of 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> is reasonable, based on operating experience, for reducing power to 50% RTP from full power conditions without challenging plant systems and allowing for rod position
determination by Required Action A.1 above.
2
B.1, B.2, B.3, and B.4
When more than one [D]RPI per group fail, additional actions are necessary to ensure that acceptable power distribution limits are maintained, minimum SDM is maintained, and the potential effects of rod misalignment on associated accident analyses are limited. Placing the Rod Control System in manual assures unplanned rod motion will not occur. Together with the indirect position determination available via in a 3 I 5 s 6 3 B 3.1.7 5 INSERT 3 If a rod has been significantly moved (in excess of 24 steps in one direction, since the position was last determined), Required Action A.1 is still appropriate but must be initiated promptly to begin verifying that the rod is still properly positioned, relative to their group positions. The allowed Completion Time of 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> provides an acceptable period of time to verify the rod position with inoperable position indicator indirectly by using movable incore detectors. This Completion Time also allows for an exception to the normal "time zero" for beginning the allowed outage time "clock." In this Required Action, the Completion Time only begins on discovery that both:
- a. One RPI per group inoperable for one or more groups; and
- b. A rod with an inoperable position indicator has been moved in excess of 24 steps in one direction since the last determination of the rod's position.
If at any time during the existence of Condition A (one RPI per group inoperable for one or more groups) a rod with an inoperable position indicator has been moved in excess of 24 steps in one direction since the last determination of the rod's position, this Completion Time begins to be tracked.
Insert Page B 3.1.7-4 Rod Position Indication B 3.1.7 WOG STS B 3.1.7-5 Rev. 3.0, 03/31/04 BASES ACTIONS (continued)
movable incore detectors will minimize the potential for rod misalignment. The immediate Completion Time for placing the Rod Control System in manual reflects the urgency with which unplanned rod motion must be prevented while in this Condition.
8 Monitoring and recording reactor coolant Tavg help assure that significant changes in power distribution and SDM are avoided. The once per hour Completion Time is acceptable because only minor fluctuations in RCS temperature are expected at steady state plant operating conditions.
The position of the rods may be determined indirectly by use of the movable incore detectors. The Required Action may also be satisfied by ensuring at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> that F Q satisfies LCO 3.2.1, satisfies LCO 3.2.2, and SHUTDOWN MARGIN is within the limits provided in the COLR, provided the nonindicating rods have not been moved. Verification of control rod position once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> is adequate for allowing continued full power operation for a limited, 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period, since the probability of simultaneously having a rod significantly out of position and an event sensitive to that rod position is small. The 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Completion Time provides sufficient time to troubleshoot and restore the
[D]RPI system to operation while avoiding the plant challenges associated with the shutdown without full rod position indication.
H N F(Required Action A.1) 6 5 INSERT 4 Based on operating experience, normal power operation does not require excessive rod movement. If one or more rods has been significantly moved, the Required Action of C.1 or C.2 below is required.
C.1 and C.2
These Required Actions clarify that when one or more rods with inoperable position indicators have been moved in excess of 24 steps in one direction, since the position was last determined, the Required Actions of A.1 and A.2, [or B.1, as applicable] are still appropriate but must be initiated promptly under Required Action C.1 to begin verifying that these rods are still properly positioned, relative to their group positions.
If, within [4] hours, the rod positions have not been determined, THERMAL POWER must be reduced to 50% RTP within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> to avoid undesirable power distributions that could result from continued operation at > 50% RTP, if one or more rods are misaligned by more than 24 steps. The allowed Completion Time of [4] hours provides an acceptable period of time to verify the rod positions.
5 5 3 I B 3.1.7 5 INSERT 4 and once within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> after a rod with an inoperable position indicator has been moved in excess of 24 steps in one direction since the last determination of the rod's position
Insert Page B 3.1.7-5 o -
Rod Position Indication B 3.1.7 WOG STS B 3.1.7-6 Rev. 3.0, 03/31/04 BASES ACTIONS (continued)
D.1.1 and D.1.2
With one demand position indicator per bank inoperable, the rod positions can be determined by the [D]RPI System. Since normal power operation does not require excessive movement of rods, verification by administrative means that the rod position indicators are OPERABLE and the most withdrawn rod and the least withdrawn rod are 12 steps apart within the allowed Completion Time of once every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> is adequate.
D.2 Reduction of THERMAL POWER to 50% RTP puts the core into a condition where rod position is not significantly affecting core peaking factor limits (Ref. 3). The allowed Completion Time of 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> provides an acceptable period of time to verify the rod positions per Required Actions C.1.1 and C.1.2 or reduce power to 50% RTP.
E.1 If the Required Actions cannot be completed within the associated Completion Time, the plant must be brought to a MODE in which the requirement does not apply. To achieve this status, the plant must be brought to at least MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. The allowed Completion Time is reasonable, based on operating experience, for reaching the required MODE from full power conditions in an orderly manner and without challenging plant systems.
I D and is not met 5 6 any 2 2 C C 5 3 5within the required rod alignment limits of LCO 3.1.4 5 SURVEILLANCE SR 3.1.7.1 REQUIREMENTS Verification that the [D]RPI agrees with the demand position within
[12] steps ensures that the [D]RPI is operating correctly. Since the [D]RPI does not display the actual shutdown rod positions between 18 and 210 steps, only points within the indicated ranges are required in
comparison.
This Surveillance is performed prior to reactor criticality after each removal of the reactor head, as there is the potential for unnecessary plant transients if the SR were performed with the reactor at power.
INSERT 5 5 B 3.1.7 5 INSERT 5 SR 3.1.7.1 is the performance of a CHANNEL CALIBRATION for each IRPI channel. The calibration verifies the accuracy of each IRPI channel.
The 18 month Frequency is based on the need to perform this Surveillance under the conditions that apply during a plant outage and the potential for unnecessary plant transients if the SR were performed with the reactor at power. Operating experience has shown these components usually pass the SR when performed at a Frequency of once every 18 months. Therefore, the Frequency was concluded to be acceptable from a reliability standpoint.
SR 3.1.7.2 SR 3.1.7.2 is the performance of a system functional test of the Demand Position Indication System. The system functional test verifies the OPERABILITY of the Demand Position Indication System.
The 18 month Frequency is based on the need to perform this Surveillance under the conditions that apply during a plant outage and the potential for unnecessary plant transients if the SR were performed with the reactor at power. Operating experience has shown these components usually pass the SR when performed at a Frequency of once every 18 months. Therefore, the Frequency was concluded to be acceptable from a reliability standpoint.
Insert Page B 3.1.7-6 Rod Position Indication B 3.1.7 WOG STS B 3.1.7-7 Rev. 3.0, 03/31/04 BASES 2REFERENCES 1. 10 CFR 50, Appendix A, GDC 13.
- 2. FSAR, Chapter [15]. USAR, Section 7.1, General Design Criteria12, "Instrumentation and Control Systems." U 14 3. FSAR, Chapter [15].
JUSTIFICATION FOR DEVIATIONS ITS 3.1.7 BASES, ROD POSITION INDICATION
- 1. ISTS 3.1.7 Bases Background references General Design Criteria. Kewaunee Power Station (KPS) was designed prior to promulgation of 10 CFR 50, Appendix A. Therefore, ITS 3.1.7 Bases Background has been revised to discuss the design standards used by KPS. Additionally, bases references to 10 CFR 50, Appendix A have been replaced with references to the appropriate section of the USAR.
- 2. Changes are made (additions, deletions, and/or changes) to the ISTS Bases which reflect the plant specific nomenclature, number, reference, system description, analysis, or licensing basis description.
- 3. The ISTS contains bracketed information and/or values that are generic to all Westinghouse vintage plants. The brackets are removed and the proper plant specific information/value is provided. This is acceptable since the generic specific information/value is revised to reflect the current plant design.
- 4. The punctuation corrections have been made consistent with the Writer's Guide from the Improved Technical Specifications, TSTF-GG-05-01, Section 5.1.3.
- 5. The Bases are changed to reflect changes made to the Specification.
- 6. Changes are made to reflect the actual Specification.
- 7. The requirement that the IRPI indicates within the agreement limit of the group step counter demand position has been deleted since the requirement is already covered by ITS LCO 3.1.4. If the agreement limit is not met, then the ACTIONS of LCO 3.1.4, "Rod Group Alignment Limits," should be entered. As written in these Bases, both the ACTIONS of ITS LCO 3.1.4 and ITS LCO 3.1.7 would have to be entered if not within the agreement limit. The appropriate ACTIONS are those of ITS LCO 3.1.4. ITS LCO 3.1.7 should only cover the actual IRPI System, not the agreement limits.
- 8. Typographical error corrected.
Kewaunee Power Station Page 1 of 1 Specific No Significant Haza rds Considerations (NSHCs)
DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATIONS ITS 3.1.7, ROD POSITION INDICATION There are no specific NSHC discussions for this Specification.
Kewaunee Power Station Page 1 of 1 ATTACHMENT 8 ITS 3.1.8, PHYSICS TESTS EXCEPTIONS - MODE 2 Current Technical Specification (CTS) Markup and Discussion of Changes (DOCs)
Amendment No. 165 TS 3.1-10 03/11/2003 f. Minimum Conditions for Criticality
- 1. The reactor shall not be brought to a critical condition until the pressure-temperature state is to the right of the criticality limit line shown in Figure TS 3.1-1.
- 2. The reactor shall be maintained subcritical by at least 1% k/k until normal water level is established in the pressurizer.
- 3. When the reactor is critical the moderator temperature coefficient shall be as specified in the COLR, except during LOW POWER PHYSICS TESTING. The maximum upper moderator temperature coefficient limit shall be 5 pcm/°F for power levels 60% RATED POWER and 0 pcm/ºF for power levels > 60% RATED POWER. 4. If the limits of 3.1.f.3 cannot be met, then power operation may continue provided the following actions are taken:
A. Within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, develop and maintain administrative control rod withdrawal limits sufficient to restore the moderator temperature coefficient to within the limits specified in TS 3.1.f.3. These withdrawal limits shall be in addition to the
insertion limits specified in TS 3.10.d.
B. If the actions specified in TS 3.1.f.4.A are not satisfied, then be in HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
A01ITS ITS 3.1.8 Page 1 of 5See ITS 3.4.3 See ITS 3.4.9 See ITS 3.1.3 L01 L01A02Add proposed ACTIONS C and D During performance of PHYSIC TESTS, the number of required channels for LCO 3.3.1, Functions 2, 3, 6, and 16.d may be reduced to 3. Add proposed LCO 3.1.8.a L01Add proposed SR 3.1.8.1 L01Add proposed SR 3.1.8.2 and SR 3.1.8.3 Add proposed ACTIONS A and B M01M01 LCO 3.1.8 and A pplicabilit y initiated in MODE 2 A03M01Add proposed LCO 3.1.8.b and LCO 3.1.8.c Add proposed suspension of LCO 3.4.2 requirement A01ITS ITS 3.1.8 C. Quadrant Power Tilt Limits
- 1. Except for physics tests, whenever the indicated quadrant power tilt ratio > 1.02, one of the following actions shall be taken within two hours:
A. Eliminate the tilt.
B. Restrict maximum core power level 2% for every 1% of indicated power tilt ratio
> 1.0. 2. If the tilt condition is not eliminated after 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, then reduce power to 50% or lower.
- 3. Except for Low Power Physics Tests, if the indicated quadrant tilt is > 1.09 and there is simultaneous indication of a misaligned rod:
A. Restrict maximum core power level by 2% of rated values for every 1% of indicated power tilt ratio > 1.0.
B. If the tilt condition is not eliminated within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, then the reactor shall be brought to a minimum load condition (30 Mwe). 4. If the indicated quadrant tilt is > 1.09 and there is no simultaneous indication of rod misalignment, then the reactor shall immediately be brought to a no load condition
(5% reactor power).
- d. Rod Insertion Limits
- 1. The shutdown rods shall be withdrawn to within the limits, specified in the COLR, when the reactor is critical or approaching criticality.
- 2. The control banks shall be limited in physical insertion; insertion limits are specified in the COLR. If any one of the control bank insertion limits is not met:
A. Within one hour, initiate boration to restore control bank insertion to within the limits specified in the COLR, and B. Restore control bank insertion to within the limits specified in the COLR within two hours of exceeding the insertion limits.
C. If any one of the conditions of TS 3.10.d.2.A or TS 3.10.d.2.B cannot be met, then withinone hour action shall be initiated to:
- Achieve HOT STANDBY within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> - Achieve HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />
- 3. Insertion limit does not apply during physics tests or during periodic exercise of individual rods. However, the shutdown margin, as specified in the COLR, must be maintained except for the Low Power Physics Test to measure control rod worth and shutdown margin. For this test, the reactor may be critical with all but one high worth
rod inserted.
LCO 3.1.8 and A pplicabilit y LCO 3.1.8
and A pplicabilit y See ITS 3.2.4 See ITS 3.1.5 See ITS 3.1.6 See ITS 3.1.5 and 3.1.6 initiated in MODE 2 A03 Amendment No. 165 TS 3.10-4 03/11/2003 Page 2 of 5 A01ITS ITS 3.1.8 e. Rod Misalignment Limitations NOTE: Individual RPIs may be outside their limits for <
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> following substantial rod movement This specification defines allowable limits for misaligned rod cluster control assemblies. In TS 3.10.e.1 and TS 3.10.e.2, the magnitude, in steps, of an indicated rod misalignment may be determined by comparison of the respective bank demand step counter to the analog individual rod position indicator, the rod position as noted on the plant process computer, or through the conditioning module output voltage via a correlation of rod position vs. voltage.
Rod misalignment limitations do not apply during physics testing.
- 1. When reactor power is 85% of rating, the rod cluster control assembly shall be maintained within +/- 12 steps from their respective banks. If a rod cluster control assembly is misaligned from its bank by more than +/- 12 steps when reactor power is 85%, then the rod will be realigned or the core power peaking factors shall be determined within four hours, and TS 3.10.b applied. If peaking factors are not determined within four hours, the reactor power shall be reduced to < 85% of rating. 2. When reactor power is < 85% but 50% of rating, the rod cluster control assemblies shall be maintained within +/- 24 steps from their respective banks. If a rod cluster control assembly is misaligned from its bank by more than +/- 24 steps when reactor power is
< 85% but 50%, the rod will be realigned or the core power peaking factors shall be determined within four hours, and TS 3.10.b applied. If the peaking factors are not determined within four hours, the reactor power shall be reduced to < 50% of rating. 3. And, in addition to TS 3.10.e.1 and TS 3.10.e.2, if the misaligned rod cluster control assembly is not realigned within eight hours, the rod shall be declared inoperable.
- f. Inoperable Rod Position Indicator Channels
NOTE: Individual RPIs may be outside their limits for <
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> following substantial rod movement
- 1. If one individual rod position indicator channel per group is inoperable for one or more groups, then perform either A or B below: (Note: Separate entry condition is allowed for
each inoperable individual rod position indicator.)
A. Verify the position of the rod cluster control indirectly by movable incore detectors each eight hours, or B. Within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> reduce reactor thermal power to 50% of RATED POWER. 2. If more than one individual rod position indicator channel per group are inoperable, then:
A. IMMEDIATELY place the control rods in manual, and B. Once per 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, monitor and record RCS Tavg , and C. Verify the position of the rod by movable incore detectors each 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, and See ITS 3.1.7 See ITS 3.1.7 See ITS 3.1.4 See ITS 3.1.4 See ITS 3.1.4 initiated in MODE 2 LCO 3.1.8 and A pplicabilit y A03 Amendment No. 181 TS 3.10-5 03/24/2005 Page 3 of 5 ITS 3.1.8 TABLE TS 3.5-2 INSTRUMENT OPERATION CONDITIONS FOR REACTOR TRIP Amendment No. 137 Page 1 of 4 06/09/98 1 2 3 4 5 6 NO. FUNCTIONAL UNIT NO. OF CHANNELS NO. OF CHANNELS TO TRIP MINIMUM OPERABLE CHANNELS MINIMUM DEGREE OF REDUNDANCY PERMISSIBLE BYPASS CONDITIONS OPERATOR ACTION IF CONDITIONS OF COLUMN 3 OR 4 CANNOT BE MET 1 Manual 2 1 1 - Maintain HOT SHUTDOWN 2 Nuclear Flux Power Range (1) Low setting 4 2 3 1 P-10 Maintain HOT SHUTDOWN High setting 4 2 3 1 Positive rate 4 2 3 1 Negative rate 4 2 3 1 3 Nuclear Flux
Intermediate Range 2 1 1 - P-10 Maintain HOT SHUTDOWN (3) 4 Nuclear Flux
Source Range 2 1 1 - P-6 Maintain HOT SHUTDOWN (3) 5 Overtemperature T 4 2 3 1 Maintain HOT SHUTDOWN 6 Overpower T 4 2 3 1 Maintain HOT SHUTDOWN 7 Low Pressurizer Pressure 4 2 3 1 P-7 Maintain HOT SHUTDOWN 8 High Pressurizer Pressure 3 2 2 - Maintain HOT SHUTDOWN
~See ITS 3.3.1 A01 LCO 3.1.8 Page 4 of 5 ITS 3.1.8 A01 TABLE TS 3.5-2 INSTRUMENT OPERATION CONDITIONS FOR REACTOR TRIP Amendment No. 195 Page 4 of 4 03/28/2008 NOTES (1) One additional channel may be taken out of service for zero power physics testing.
(2) Deleted
(3) When a block condition exists, maintain normal operation.
(4) Underfrequency on the 4-kV buses trips the Reactor Coolant Pump breakers, which in turn trips the reactor when power is ab ove P-7. Permissive/Interlock Channels Coincidence Setting Limit P-6 Intermediate Range Nuclear Instrument 1 of 2 > 10-5% RATED POWER P-7 Power Range Nuclear Instrument 3 of 4 AND 2 of 2 12.2% RATED POWER Turbine Impulse Pressure 12.2% RATED POWER (a) P-8 Power Range Nuclear Instrument 3 of 4 < 10% RATED POWER P-10 Power Range Nuclear Instrument 2 of 4 7.8% RATED POWER (a) Setting Limit is converted to an equivalent turbine impulse pressure See ITS 3.3.1 M02 Page 4 of 15 Page 5 of 5 DISCUSSION OF CHANGES ITS 3.1.8, PHYSICS TESTS Exceptions - MODE 2 Kewaunee Power Station Page 1 of 3 ADMINISTRATIVE CHANGES A01 In the conversion of the Kewaunee Power Station (KPS) Current Technical Specifications (CTS) to the plant specific Improved Technical Specifications (ITS), certain changes (wording preferences, editorial changes, reformatting, revised numbering, etc.) are made to obtain consistency with NUREG-1431, Rev. 3.0, "Standard Technical Specifications-Westinghouse Plants" (ISTS).
These changes are designated as administrative changes and are acceptable because they do not result in technical changes to the CTS.
A02 CTS 3.1.f.3, CTS 3.10.d.3, and CTS 3.10.e state that the limitations of certain specifications may be suspended during the performance of PHYSICS TESTS. CTS Table TS 3.5-2, Functional Units 2, Nuclear Flux Power Range, states the minimum OPERABLE channel requirement is 3, except as modified by Note (1). ITS LCO 3.1.8 includes an allowance to reduce the required number of channels for ITS LCO 3.3.1, "RPS Instrumentation," Functions 2 (Power Range Neutron Flux), 3 (Power Range Neutron Flux Rate), 6 (Overtemperature T), and 16.d (Power Range Neutron Flux, P-10) from "4" to "3" during PHYSICS TESTS. This changes the CTS by stating the specific number of RPS channels from that have to be OPERABLE during PHYSICS TESTS.
The purpose of CTS 3.1.f.3, CTS 3.10.d.3, and CTS 3.10.e is to allow some flexibility during the performance of PHYSIC TESTS. This change is acceptable because the minimum number of channels required for OPERABILITY for the Reactor Trip Functions in CTS Table TS 3.5-2 is currently "3." This allowance is needed since the Required Channels in ITS 3.3.1, Reactor Trip System Instrumentation, is "4." This change from the CTS is discussed in the Discussion of Changes for ITS 3.3.1. Furthermore, the exception identified in CTS Table TS 3.5-2 Note (1) is discussed in DOC M02. This change is designated as administrative because it does not result in technical changes to the CTS.
A03 CTS 3.1.f.3 states that the Moderator Temperature Coefficient requirement specified in the COLR may be suspended during the performance of LOW POWER PHYSICS TESTING. CTS 3.10.d.3 states that the Rod Insertion Limits do not apply during the performance of PHYSICS TESTS. CTS 3.10.e states that the Rod Misalignment Limitations do not apply during the performance of PHYSICS TESTS. ITS 3.1.8 is applicable "During PHYSICS TESTS initiated in MODE 2." This changes the CTS such that the Specification is applicable in MODE 2 only when a PHYSICS TEST is initiated.
The purpose of ITS 3.1.8 Applicability is to ensure that the Actions contained in the Specification are followed. The CTS applicability does not specifically state what MODE the PHYSICS TEST is performed in. The ITS Applicability states emphatically the MODE that the PHYSICS TEST will be performed. This change is designated as administrative because it clarifies the current wording in the Specification with no change in intent.
DISCUSSION OF CHANGES ITS 3.1.8, PHYSICS TESTS Exceptions - MODE 2 Kewaunee Power Station Page 2 of 3 MORE RESTRICTIVE CHANGES M01 TS 3.1.f, CTS 3.10.d.3, and CTS 3.10.e state that the limitations of certain specifications may be suspended during the performance of PHYSICS TESTS but does not provide restrictions that must be followed when utilizing the CTS exceptions. ITS 3.1.8 provides the requirements and restrictions for performing testing during PHYSICS TESTS initiated in MODE 2. A Surveillance (SR 3.1.8.3) to verify the SHUTDOWN MARGIN is within limits specified in the COLR every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and an ACTION (ACTION A) to follow if the SHUTDOWN MARGIN is not met are added. Additionally, a Surveillance (SR 3.1.8.2) to verify that THERMAL POWER is 5% RTP every 30 minutes and an ACTION (ACTION B) to follow if the THERMAL POWER is not within limit (i.e., it is not 5% RTP) has been added. This changes the CTS by imposing additional requirements on the application of the test exception LCO.
This change is acceptable because it imposes reasonable restrictions on the performance of PHYSICS TESTS when the control rod and RCS minimum temperature Specifications are allowed to be violated. When the control rod and RCS minimum temperature Specifications are allowed to be violated, additional actions must be taken to ensure that sufficient SHUTDOWN MARGIN is available to shutdown the reactor and keep it subcritical if needed when in MODE 2 with k eff > 1.0. This change is designated as more restrictive because it imposes additional restrictions not found in the CTS.
M02 CTS Table TS 3.5-2, Functional Unit 2, Nuclear Flux Power Range, requires three channels to be OPERABLE. However, Note (1) allows one additional channel to be taken out of service during zero power testing. Thus, during zero power PHYSICS TESTS, the CTS only requires two Functional Unit 2 channels to be OPERABLE. ITS LCO 3.1.8, in part, includes an allowance to reduce the required number of channels for ITS LCO 3.3.1, "RPS Instrumentation,"
Functions 2 (Power Range Neutron Flux) and 3 (Power Range Neutron Flux Rate) from "4" to "3" during PHYSICS TESTS. This changes the CTS by always requiring three channels of Nuclear Flux Power Range be OPERABLE during all MODE 2 PHYSICS TESTS, even zero power PHYSICS TESTS.
The purpose of CTS Table TS 3.5-2 Note (1) is to allow flexibility during performance of zero power PHYSICS TESTS. However, there are four installed Nuclear Flux Power Range channels, and ITS LCO 3.1.8 already allows one of them to be inoperable during PHYSICS TESTS. Thus, flexibility is being provided in LCO 3.1.8, and an additional channel being inoperable is not necessary. This change is designated as more restrictive since an additional channel is required during zero power PHYSICS TESTS.
RELOCATED SPECIFICATIONS None
DISCUSSION OF CHANGES ITS 3.1.8, PHYSICS TESTS Exceptions - MODE 2 Kewaunee Power Station Page 3 of 3 REMOVED DETAIL CHANGES None
LESS RESTRICTIVE CHANGES
L01 (Category 1 - Relaxation of LCO Requirements) CTS 3.10.f.1 (ITS 3.4.2, " RCS Minimum Temperature for Criticality") states that the reactor shall not be brought to a critical condition until the pressure-temperature state is to the right of the criticality limit line shown in Figure TS 3.1-1. ITS 3.1.8 provides an exception to LCO 3.4.2, "RCS Minimum Temperature for Criticality," provided the RCS lowest loop average temperature is 530ºF. A Surveillance Requirement (SR 3.1.8.1) to verify the RCS lowest loop average temperature is 530ºF every 30 minutes has been added. In addition, ACTION C has been added to cover the situation when RCS lowest loop average temperature is not within limit. The Required Action is to restore RCS lowest loop average temperature to within limit within 15 minutes. If this is not met, then ACTION D requires the unit to be in MODE 3 within 15 minutes. This changes the CTS by allowing the suspension of LCO 3.4.2, "RCS Minimum Temperature for Criticality." However, it places a limitation on the RCS lowest loop average temperature.
This change is acceptable because the LCO requirements continue to ensure that the process variables are maintained consistent with the safety analyses and licensing basis. This changes the CTS by allowing the suspension of LCO 3.4.2, "RCS Minimum Temperature for Criticality." However, it places a limitation on the RCS lowest loop average temperature. The limit on RCS average temperature is provided in the test exception LCO to ensure that the RCS temperature stays within the analyzed range. This change is designated as less restrictive because less stringent LCO requirements are being applied in the ITS than were applied in the CTS.
Improved Standard Technical Specifications (ISTS) Markup and Justification for Deviations (JFDs)
PHYSICS TESTS Exceptions - MODE 2 3.1.8 WOG STS 3.1.8-1 Rev. 3.0, 03/31/04 CTS 3.1 REACTIVITY CONTROL SYSTEMS
3.1.8 PHYSICS
TESTS Exceptions - MODE 2
LCO 3.1.8 During the performance of PHYSICS TESTS, the requirements of:
LCO 3.1.3, "Moderator Temperature Coefficient,"
LCO 3.1.4, "Rod Group Alignment Limits,"
LCO 3.1.5, "Shutdown Bank Insertion Limits," LCO 3.1.6, "Control Bank Insertion Limits," and LCO 3.4.2, "RCS Minimum Temperature for Criticality"
may be suspended and the number of required channels for LCO 3.3.1, "RTS Instrumentation," Functions 2, 3, 6 and 18.e, may be reduced to 3 required channels, provided:
- a. RCS lowest loop average temperature is [531]°F, b. SDM is within the limits specified in the COLR, and
- c. THERMAL POWER is <
5% RTP.
APPLICABILITY: During PHYSICS TESTS initiated in MODE 2.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME
A. SDM not within limit.
A.1 Initiate boration to restore SDM to within limit.
AND A.2 Suspend PHYSICS TESTS exceptions.
15 minutes
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> B. THERMAL POWER not within limit.
B.1 Open reactor trip breakers.
Immediately
C. RCS lowest loop average temperature not within limit.
C.1 Restore RCS lowest loop average temperature to within limit.
15 minutes 3.1.f 3.10.e 3.10.d 3.10.d DOC L01 DOC L01 DOC M01 DOC M01 DOC A02 3.1.f, 3.10.e, 3.10.d, DOC L01 DOC M01 DOC M01 DOC L01 ; ;; 1 2 1 RPS 16.d 4 530 PHYSICS TESTS Exceptions - MODE 2 3.1.8 WOG STS 3.1.8-2 Rev. 3.0, 03/31/04 CTS ACTIONS (continued)
CONDITION REQUIRED ACTION COMPLETION TIME D. Required Action and associated Completion
Time of Condition C not met. D.1 Be in MODE 3.
15 minutes DOC L01
SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY
SR 3.1.8.1 Perform a CHANNEL OPERATIONAL TEST on power range and intermediate range channels per
[SR 3.3.1.7, SR 3.3.1.8, and Table 3.3.1-1].
Prior to initiation of PHYSICS TESTS SR 3.1.8.2 Verify the RCS lowest loop average temperature is [531]°F.
30 minutes SR 3.1.8.3 Verify THERMAL POWER is 5% RTP. 30 minutes
SR 3.1.8.4 Verify SDM is within the limits specified in the COLR.
24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> 3 3 2DOC L01 2 1 530 3DOC M01 3DOC M01 3 JUSTIFICATION FOR DEVIATIONS ITS 3.1.8, PHYSICS TESTS Exceptions - MODE 2
- 1. The punctuation corrections have been made consistent with the Writer's Guide from the Improved Technical Specifications, TSTF-GG-05-01, Section 5.1.3.
- 2. The ISTS contains bracketed information and/or values that are generic to all Westinghouse vintage plants. The brackets are removed and the proper plant specific information/value is provided. This is acceptable since the generic specific information/value is revised to reflect the current plant design.
- 3. ISTS SR 3.1.8.1 requires a CHANNEL OPERATIONAL TEST be performed on the Intermediate and Power Range Channels "prior to initiation of PHYSICS TESTS." However, no finite time as to how soon prior to the PHYSICS TESTS is stated. The ITS Applicability for the Intermediate and Power Range channels includes MODE 2, thus the normal, periodic Frequencies for SR 3.3.1.7 and SR 3.3.1.8 must be met prior to entering MODE 2. Therefore, the normal periodic Frequencies already ensure the "prior to initiation of PHYSICS TEST" is met, and ISTS SR 3.1.8.1 is not necessary and has been deleted. Due to this deletion, the remaining SRs have been renumbered.
- 4. Changes made to be consistent with changes made to LCO 3.3.1.
Kewaunee Power Station Page 1 of 1 Improved Standard Technical Specifications (ISTS) Bases Markup and Bases Justification for Deviations (JFDs)
PHYSICS TESTS Exceptions - MODE 2 B 3.1.8 WOG STS B 3.1.8-1 Rev. 3.0, 03/31/04 B 3.1 REACTIVITY CONTROL SYSTEMS
B 3.1.8 PHYSICS TESTS Exceptions - MODE 2
BASES BACKGROUND The primary purpose of the MODE 2 PHYSICS TESTS exceptions is to permit relaxations of existing LCOs to allow certain PHYSICS TESTS to
be performed.
Section XI of 10 CFR 50, Appendix B (Ref. 1), requires that a test program be established to ensure that structures, systems, and components will perform satisfactorily in service. All functions necessary to ensure that the specified design conditions are not exceeded during normal operation and anticipated operational occurrences must be tested. This testing is an integral part of the design, construction, and operation of the plant. Requirements for notification of the NRC, for the purpose of conducting tests and experiments, are specified in 10 CFR 50.59 (Ref. 2).
The key objectives of a test program are to (Ref. 3):
- a. Ensure that the facility has been adequately designed, 1
- b. Validate the analytical models used in the design and analysis, ; 1 c. Verify the assumptions used to predict unit response, d. Ensure that installation of equipment in the facility has been accomplished in accordance with the design, and
- e. Verify that the operating and emergency procedures are adequate.
- ; ;1 1 To accomplish these objectives, testing is performed prior to initial criticality, during startup, during low power operations, during power ascension, at high power, and after each refueling. The PHYSICS TESTS requirements for reload fuel cycles ensure that the operating characteristics of the core are consistent with the design predictions and that the core can be operated as designed (Ref. 4).
PHYSICS TESTS procedures are written and approved in accordance with established formats. The procedures include all information necessary to permit a detailed execution of the testing required to ensure that the design intent is met. PHYSICS TESTS are performed in accordance with these procedures and test results are approved prior to continued power escalation and long term power operation.
PHYSICS TESTS Exceptions - MODE 2 B 3.1.8 WOG STS B 3.1.8-2 Rev. 3.0, 03/31/04 BASES BACKGROUND (continued)
The PHYSICS TESTS required for reload fuel cycles (Ref. 4) in MODE 2 are listed below:
- a. Critical Boron Concentration - Control Rods Withdrawn,
- b. Critical Boron Concentration - Control Rods Inserted,
- c. Control Rod Worth,
- d. Isothermal Temperature Coefficient (ITC), and
- e. Neutron Flux Symmetry.
- ; ;.1 1 1 1 2Differential Boron Worth 2 2The first four tests are performed in MODE 2, and the last test can be performed in either MODE 1 or 2. These and other supplementary tests may be required to calibrate the nuclear instrumentation or to diagnose operational problems. These tests may cause the operating controls and process variables to deviate from their LCO requirements during their performance.
[ a. The Critical Boron Concentration - Control Rods Withdrawn Test measures the critical boron concentration at hot zero power (HZP). With all rods out, the lead control bank is at or near its fully withdrawn position. HZP is where the core is critical (k eff = 1.0), and the Reactor Coolant System (RCS) is at design temperature and pressure for zero power. Performance of this test should not violate any of the referenced LCOs.
3 b. The Critical Boron Concentration - Control Rods Inserted Test measures the critical boron concentration at HZP, with a bank having
a worth of at least 1% k/k when fully inserted into the core. This test is used to measure the boron reactivity coefficient. With the core at HZP and all banks fully withdrawn, the boron concentration of the reactor coolant is gradually lowered in a continuous manner. The selected bank is then inserted to make up for the decreasing boron concentration until the selected bank has been moved over its entire
range of travel. The reactivity re sulting from each incremental bank movement is measured with a reactivity computer. The difference between the measured critical boron concentration with all rods fully withdrawn and with the bank inserted is determined. The boron INSERT 1 3 B 3.1.8 1 INSERT 1 The Differential Boron Worth Test determines if the measured differential boron worth is consistent with the predicted value. With the core at HZP, the change in equilibrium boron concentration is determined at different rod bank positions. As the rod bank or banks are moved, the reactivity change is measured using a reactivity computer. The measured reactivity change is divided by the difference in measured critical boron concentrations to determine the differential boron worth. Insert Page B 3.1.8-2 PHYSICS TESTS Exceptions - MODE 2 B 3.1.8 WOG STS B 3.1.8-3 Rev. 3.0, 03/31/04 BASES BACKGROUND (continued)
reactivity coefficient is determined by dividing the measured bank worth by the measured boron concentration difference. Performance of this test could violate LCO 3.1.4, "Rod Group Alignment Limits,"
LCO 3.1.5, "Shutdown Bank Insertion Limit," or LCO 3.1.6, "Control
Bank Insertion Limits." 3 c. The Control Rod Worth Test is used to measure the reactivity worth of selected control banks. This test is performed at HZP and has three alternative methods of performance. The first method, the Boron Exchange Method, varies the reactor coolant boron concentration and moves the selected control bank in response to the changing boron concentration. The reactivity changes are measured with a reactivity computer. This sequence is repeated for the remaining control banks. The second method, the Rod Swap Method, measures the worth of a predetermined reference bank using the Boron Exchange Method above. The reference bank is then nearly fully inserted into the core. The selected bank is then inserted into the core as the reference bank is withdrawn. The HZP critical conditions are then determined with the selected bank fully inserted into the core. The worth of the selected bank is inferred, based on the position of the reference bank with respect to the selected bank. This sequence is repeated as necessary for the remaining control banks. The third method, the Boron Endpoint Method, moves the selected control bank over its entire length of travel and then varies the reactor coolant boron concentration to achieve HZP criticality again. The difference in boron concentration is the worth of the selected control bank. This sequence is repeated for the remaining control banks. Performance of this test could violate LCO 3.1.4, LCO 3.1.5, or LCO 3.1.6.
- d. The ITC Test measures the ITC of the reactor. This test is performed at HZP and has two methods of performance. The first method, the Slope Method, varies RCS temperature in a slow and continuous manner. The reactivity change is measured with a reactivity computer as a function of the temperature change. The ITC is the slope of the reactivity versus the temperature plot. The test is repeated by reversing the direction of the temperature change, and the final ITC is the average of the two calculated ITCs. The second method, the Endpoint Method, changes the RCS temperature and measures the reactivity at the beginning and end of the
PHYSICS TESTS Exceptions - MODE 2 B 3.1.8 WOG STS B 3.1.8-4 Rev. 3.0, 03/31/04 BASES BACKGROUND (continued)
temperature change. The ITC is the total reactivity change divided by the total temperature change. The test is repeated by reversing the direction of the temperature change, and the final ITC is the average of the two calculated ITCs. Performance of this test could violate LCO 3.4.2, "RCS Minimum Temperature for Criticality." e. The Flux Symmetry Test measures the degree of azimuthal symmetry of the neutron flux at as low a power level as practical, depending on the test method employed. This test can be performed at HZP (Control Rod Worth Symmetry Method) or at 30% RTP (Flux Distribution Method). The Control Rod Worth Symmetry Method inserts a control bank, which can then be withdrawn to compensate for the insertion of a single control rod from a symmetric set. The symmetric rods of each set are then tested to evaluate the symmetry of the control rod worth and neutron flux (power distribution). A reactivity computer is used to measure the control rod worths. Performance of this test could violate LCO 3.1.4, LCO 3.1.5, or LCO 3.1.6. The Flux Distribution Method uses the incore flux detectors to measure the azimuthal flux distribution at selected locations with the core at 30% RTP. ]
3 APPLICABLE The fuel is protected by LCOs that preserve the initial conditions of the SAFETY core assumed during the safety analyses. The methods for development ANALYSES of the LCOs that are excepted by this LCO are described in the Westinghouse Reload Safety Evaluation Methodology Report (Ref. 5). The above mentioned PHYSICS TESTS, and other tests that may be required to calibrate nuclear instrumentation or to diagnose operational problems, may require the operating control or process variables to deviate from their LCO limitations.
2Reference 5 The FSAR defines requirements for initial testing of the facility, including PHYSICS TESTS. Tables [14.1-1 and 14.1-2] summarize the zero, low power, and power tests. Requirements for reload fuel cycle PHYSICS TESTS are defined in ANSI/ANS-19.6.1-1985 (Ref. 4). Although these PHYSICS TESTS are generally accomplished within the limits for all LCOs, conditions may occur when one or more LCOs must be suspended to make completion of PHYSICS TESTS possible or practical. This is acceptable as long as the fuel design criteria are not violated. When one or more of the requirements specified in LCO 3.1.3, "Moderator Temperature Coefficient (MTC)," LCO 3.1.4, LCO 3.1.5, LCO 3.1.6, and LCO 3.4.2 are suspended for PHYSICS TESTS, the fuel design criteria are preserved as long as the power level is limited to 5% RTP, the reactor coolant temperature is kept 531°F, and SDM is within the limits provided in the COLR.
U 2 4 13.3-1 s 530 PHYSICS TESTS Exceptions - MODE 2 B 3.1.8 WOG STS B 3.1.8-5 Rev. 3.0, 03/31/04 BASES APPLICABLE SAFETY ANALYSES (continued)
The PHYSICS TESTS include measurement of core nuclear parameters or the exercise of control components that affect process variables. Among the process variables involved are AFD and QPTR, which represent initial conditions of the unit safety analyses. Also involved are the movable control components (control and shutdown rods), which are required to shut down the reactor. The limits for these variables are specified for each fuel cycle in the COLR.
As described in LCO 3.0.7, compliance with Test Exception LCOs is optional, and therefore no criteria of 10 CFR 50.36(c)(2)(ii) apply. Test Exception LCOs provide flexibility to perform certain operations by appropriately modifying requirements of other LCOs. A discussion of the criteria satisfied for the other LCOs is provided in their respective Bases.
Reference 6 allows special test exceptions (STEs) to be included as part of the LCO that they affect. It was decided, however, to retain this STE as a separate LCO because it was less cumbersome and provided additional clarity.
LCO This LCO allows the reactor parameters of MTC and minimum temperature for criticality to be outside their specified limits. In addition, it allows selected control and shutdown rods to be positioned outside of their specified alignment and insert ion limits. One power range neutron flux channel may be bypassed, reducing the number of required channels from 4 to 3. Operation beyond specified limits is permitted for the purpose of performing PHYSICS TESTS and poses no threat to fuel
integrity, provided the SRs are met.
The requirements of LCO 3.1.3, LCO 3.1.4, LCO 3.1.5, LCO 3.1.6, and LCO 3.4.2 may be suspended and the number of required channels for LCO 3.3.1, "RTS Instrumentation," Functions 2, 3, 6 and 18.e may be reduced to 3 required channels during the performance of PHYSICS
TESTS provided:
- a. RCS lowest loop average temperature is [531]°F, b. SDM is within the limits provided in the COLR, and
- c. THERMAL POWER is 5% RTP. 1 1 3; ; RPS 16.d 4 530 PHYSICS TESTS Exceptions - MODE 2 B 3.1.8 WOG STS B 3.1.8-6 Rev. 3.0, 03/31/04 BASES APPLICABILITY This LCO is applicable when performing low power PHYSICS TESTS. The Applicability is stated as "during PHYSICS TESTS initiated in MODE 2" to ensure that the 5% RTP maximum power level is not exceeded. Should the THERMAL POWER exceed 5% RTP, and consequently the unit enter MODE 1, this Applicability statement prevents exiting this Specification and its Required Actions.
ACTIONS A.1 and A.2
If the SDM requirement is not met, boration must be initiated promptly. A Completion Time of 15 minutes is adequate for an operator to correctly align and start the required systems and components. The operator should begin boration with the best source available for the plant conditions. Boration will be continued until SDM is within limit.
Suspension of PHYSICS TESTS exceptions requires restoration of each of the applicable LCOs to within specification.
B.1 When THERMAL POWER is > 5% RTP, the only acceptable action is to open the reactor trip breakers (RTBs) to prevent operation of the reactor beyond its design limits. Immediately opening the RTBs will shut down the reactor and prevent operation of the reactor outside of its design limits.
C.1 When the RCS lowest Tavg is < 531°F, the appropriate action is to restore Tavg to within its specified limit. The allowed Completion Time of 15 minutes provides time for restoring Tavg to within limits without allowing the plant to remain in an unacceptable condition for an extended period of time. Operation with the reactor critical and with temperature below 531°F could violate the assumptions for accidents analyzed in the safety analyses.
530 4 530 4 PHYSICS TESTS Exceptions - MODE 2 B 3.1.8 WOG STS B 3.1.8-7 Rev. 3.0, 03/31/04 BASES ACTIONS (continued)
D.1 If the Required Actions cannot be completed within the associated Completion Time, the plant must be brought to a MODE in which the requirement does not apply. To achieve this status, the plant must be brought to at least MODE 3 within an additional 15 minutes. The Completion Time of 15 additional minutes is reasonable, based on operating experience, for reaching MODE 3 in an orderly manner and without challenging plant systems.
SURVEILLANCE SR 3.1.8.1 REQUIREMENTS
The power range and intermediate range neutron detectors must be verified to be OPERABLE in MODE 2 by LCO 3.3.1, "Reactor Trip System (RTS) Instrumentation." A CHANNEL OPERATIONAL TEST is performed on each power range and intermediate range channel prior to initiation of the PHYSICS TESTS. This will ensure that the RTS is properly aligned to provide the required degree of core protection during the performance of the PHYSICS TESTS.
SR 3.1.8.2 Verification that the RCS lowest loop Tavg is 531°F will ensure that the unit is not operating in a condition that could invalidate the safety analyses. Verification of the RCS temperature at a Frequency of 30 minutes during the performance of the PHYSICS TESTS will ensure that the initial conditions of the safety analyses are not violated.
4 530 4 1 4 SR 3.1.8.3 2 4 Verification that the THERMAL POWER is 5% RTP will ensure that the plant is not operating in a condition that could invalidate the safety analyses. Verification of the THERMAL POWER at a Frequency of 30 minutes during the performance of the PHYSICS TESTS will ensure that the initial conditions of the safety analyses are not violated.
PHYSICS TESTS Exceptions - MODE 2 B 3.1.8 WOG STS B 3.1.8-8 Rev. 3.0, 03/31/04 BASES SURVEILLANCE REQUIREMENTS (continued)
SR 3.1.8.4 3 4 The SDM is verified by performing a reactivity balance calculation, considering the following reactivity effects:
- d. Fuel burnup based on gross thermal energy generation, ;1 ; e. Xenon concentration, 1
- f. Samarium concentration, ;1 g. Isothermal temperature coefficient (ITC), when below the point of adding heat (POAH), ;1 h. Moderate defect, when above the POAH, and
- 1 ; i. Doppler defect, when above the POAH.
Using the ITC accounts for Doppler reactivity in this calculation when the reactor is subcritical or critical but below the POAH, and the fuel temperature will be changing at the same rate as the RCS.
The Frequency of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is based on the generally slow change in required boron concentration and on the low probability of an accident occurring without the required SDM.
REFERENCES 1. 10 CFR 50, Appendix B, Section XI.
- 2. 10 CFR 50.59.
- 3. Regulatory Guide 1.68, Revision 2, August, 1978.
- 4. ANSI/ANS-19.6.1-1985, December 13, 1985.
2 5. WCAP-9273-NP-A, "Westinghouse Reload Safety Evaluation Methodology Report," July 1985.
- 6. WCAP-11618, including Addendum 1, April 1989.
DOM-NAF-5, Revision 0.0, "Application of Dominion Nuclear Core Design and Safety Analysis Methods to the Kewaunee Power Station," July 2006.
JUSTIFICATION FOR DEVIATIONS ITS 3.1.8 BASES, PHYSICS TESTS Exceptions - MODE 2
- 1. The punctuation corrections have been made consistent with the Writer's Guide from the Improved Technical Specifications, TSTF-GG-05-01, Section 5.1.3.
- 2. Changes are made (additions, deletions, and/or changes) to the ISTS Bases which reflect the plant specific nomenclature, number, reference, system description, analysis, or licensing basis description.
- 3. The ISTS contains bracketed information and/or values that are generic to all Westinghouse vintage plants. The brackets are removed and the proper plant specific information/value is provided. This is acceptable since the generic specific information/value is revised to reflect the current plant design.
- 4. The Bases are changed to reflect changes made to the Specification.
Kewaunee Power Station Page 1 of 1 Specific No Significant Haza rds Considerations (NSHCs)
DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATIONS ITS 3.1.8, PHYSICS TESTS Exceptions - MODE 2 There are no specific NSHC discussions for this Specification.
Kewaunee Power Station Page 1 of 1 ATTACHMENT 9 RELOCATED/DELETED CURRENT TECHNICAL SPECIFICATIONS
CTS 3.2.a, CHEMICAL AND VOLUME CONTROL SYSTEM Current Technical Specification (CTS) Markup and Discussion of Changes (DOCs)
CTS 3.2.a3.2 CHEMICAL AND VOLUME CONTROL SYSTEM APPLICABILITY Amendment No. 116 TS 3.2-1 03/28/95 Applies to the operational status of the Chemical and Volume Control System.
OBJECTIVE To define those conditions of the Chemical and Volume Control System necessary to ensure safe reactor operation.
SPECIFICATIONS
- a. When fuel is in the reactor there shall be at least one flow path to the core for boric acid injection.
R01 Page 1 of 1 DISCUSSION OF CHANGES CTS 3.2.a, CHEMICAL VOLUME CONTROL SYSTEM ADMINISTRATIVE CHANGES None
MORE RESTRICTIVE CHANGES
None
RELOCATED SPECIFICATIONS
R01 CTS 3.2.a provides requirements on boric acid flow paths to the reactor core although the specification is labeled "Chemical and Volume Control System."
The purpose for a boric acid flow path is for control of the chemical neutron absorber (boron) concentration in the Reactor Coolant System (RCS) and to help maintain the SHUTDOWN MARGIN. To accomplish this, the CTS requires at least one flow path to the core for boric acid injection. The Chemical and Volume Control System is not assumed to be OPERABLE to mitigate the consequences of a design basis accident (DBA) or transient. In the case of a malfunction of the CVCS, which causes a boron dilution event, the automatic response, or that required by the operator, is to close the appropriate valves in the reactor makeup system. This action is required before the shutdown margin is lost. Operation of the boration subsystem is not assumed to mitigate this event (KPS USAR Section 14.1.4). The ITS does not include this Specification. This changes the CTS by relocating this Specification to the Technical Requirements Manual (TRM).
This change is acceptable because CTS 3.2.a does not meet the 10 CFR 50.36(c)(2)(ii) criteria for inclusion into the ITS.
10 CFR 50.36(c)(2)(ii) Criteria Evaluation:
- 1. The Chemical and Volume Control System is not used to detect, and indicate in the control room, a significant degradation of the reactor coolant pressure boundary. The Chemical and Volume Control System does not satisfy criterion 1.
- 2. The Chemical and Volume Control System is not a process variable, design feature, or operating restriction that is an initial condition of a DBA or transient analysis that either assumes the failure of or presents a challenge to the integrity of a fission product barrier. The Chemical and Volume Control System does not satisfy criterion 2.
- 3. The Chemical and Volume Control System is not a structure, system, or component that is part of the primary success path and which functions or actuates to mitigate a DBA or transient that either assumes the failure of or presents a challenge to the integrity of a fission product barrier. The
Chemical and Volume Control System does not satisfy criterion 3.
Kewaunee Power Station Page 1 of 2 DISCUSSION OF CHANGES CTS 3.2.a, CHEMICAL VOLUME CONTROL SYSTEM Kewaunee Power Station Page 2 of 2
- 4. As discussed in Section 4.0 (Appendix A, page A-6) and summarized in Table 1 of WCAP-11618, the loss of the Chemical and Volume Control System (i.e., boric acid flow path to the core - operating and shutdown)was found to be a non-significant risk contributor to core damage frequency and offsite releases. Dominion Energy Kewaunee (DEK) has reviewed this evaluation, considers it applicable to Kewaunee Power Station (KPS), and concurs with the assessment. The Chemical and Volume Control System does not satisfy criterion 4.
Since 10 CFR 50.36(c)(2)(ii) criteria have not been met, the Chemical and Volume Control System may be relocated out of the Technical Specifications. The Chemical and Volume Control System will be relocated to the TRM. Changes to the TRM will be controlled by the provisions of 10 CFR 50.59. This change is designated as relocation because the Specification did not meet the criteria in 10 CFR 50.36(c)(2)(ii) and has been relocated to the TRM.
REMOVED DETAIL CHANGES
None
LESS RESTRICTIVE CHANGES None
Specific No Significant Haza rds Considerations (NSHCs)
DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATIONS CTS 3.2.a, CHEMICAL AND VOLUME CONTROL SYSTEM There are no specific NSHC discussions for this Specification.
Kewaunee Power Station Page 1 of 1