ML072200468
ML072200468 | |
Person / Time | |
---|---|
Site: | Davis Besse ![]() |
Issue date: | 08/03/2007 |
From: | FirstEnergy Nuclear Operating Co |
To: | Office of Nuclear Reactor Regulation |
References | |
Download: ML072200468 (132) | |
Text
Attachment 1, Volume 7, Rev. 0, Page 1 of 132 ATTACHMENT 1 VOLUME 7 DAVIS-BESSE IMPROVED TECHNICAL SPECIFICATIONS CONVERSION ITS SECTION 3.2 POWER DISTRIBUTION LIMITS Revision 0 Attachment 1, Volume 7, Rev. 0, Page 1 of 132
Attachment 1, Volume 7, Rev. 0, Page 2 of 132 LIST OF ATTACHMENTS
- 1. ITS 3.2.1
- 2. ITS 3.2.2
- 3. ITS 3.2.3
- 4. ITS 3.2.4
- 5. ITS 3.2.5 Attachment 1, Volume 7, Rev. 0, Page 2 of 132
Attachment 1, Volume 7, Rev. 0, Page 3 of 132 ATTACHMENT I ITS 3.2.1, REGULATING ROD INSERTION LIMITS Attachment 1, Volume 7, Rev. 0, Page 3 of 132
, Volume 7, Rev. 0, Page 4 of 132 Current Technical Specification (CTS) Markup and Discussion of Changes (DOCs)
Attachment 1, Volume 7, Rev. 0, Page 4 of 132
Attachment 1, Volume 7, Rev. 0, Page 5 of 132 ITS 3.2.1 ITS REACTIVITY CONTROL SYSTEMS REGULATING ROD INSERTION LIMITS LIMITING CONDITION FOR OPERATION LCO 3.1.3.6 The regulating rod groups shall be positioned within the acceptable 32.1 operating limits for regulating rod position provided in the CORE OPERATING LII4TS REPORT.
APPLICABILITY: MODES l1and 21 ACTION:
ACTION A ACTION D With the regulating rod groups inserted beyond the operating limits (in a recion other than acceptable operation), jor with any group sequence or overlap ACTION CF--- _tside the limits Provided in the CORE OPERATING LIMITS REPORT except for LCO Note}--
s~urveillance testing pursuant to Specification 4.1.3.1.2. either: jddproposedRequired
- ~LctionsEA.1 and C.1 Required Actions A.2. a. Restore the regulating groups to within the limits rovided in C.2, and the CORE OPERATING LIMITS REPORT within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, or D.2.1
- b. Reduce THERMAL POWER to less than or equal to that fraction of ACTION B, RATED THERMAL POWER which is allowed by the rod group position Required Actiol limits provided in the CORE OPERATING LIMITS REPORT within 2 ours, D.2.2 or ACTION E c. Be in at least HOT STANDBY within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
ACTION D NOTE: If in unacceptable region, also see Section 3/4.1.1.1.
I A02 I Npf Hal test E-Aception .3. EU. I-4fl J.IL. . \
th Ký =!l0 MO01 DAVIS-BESSE. UNIT 1 3/4 1-26 Amendment No. ,
09,00,IZý, 144 Page 1 of 3 Attachment 1, Volume 7, Rev. 0, Page 5 of 132
Attachment 1, Volume 7, Rev. 0, Page 6 of 132 ITS 3.2.1 ITS Q
REACTIVITY COUfTROL SYSTEMS REGULATING ROD INSERTION LIMITS SURVEILLANCE R~EQUIREMENTS SR 3,2.1.1. 4.1.3.6 The position of each regulating group shall be determined to be SR 3.2.1.2 within the limits rovided in the CORE OPERATING LIMITS REPORT at least once every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> ex- pt when:
- a. The reg lating rod insertion limit alarm is ino-erable, then verify the groups to be within the insertion 1 mits at least I once p r 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />; L02
- b. The c ntrol rod drive sequence alarm is inope able, then verif the groups to be within the sequence d overlap limi s at least once per 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.
DAVIS-BESSE, UNIT 1 3/4 1-27 Amendment No. 144 (next page is 3/4 1-30)
Page 2 of 3 Attachment 1, Volume 7, Rev. 0, Page 6 of 132
Attachment 1, Volume 7, Rev. 0, Page 7 of 132 ITS 3.2.1 ITS 3/4.1 REACTIVITY CONTROL SYSTEMS See ITS 3.1.1, 3/4.1.1 BORATION CONTROL ITS 3.1.8, SHUTDOWN MARGIN See LIMITING CONDITION FOR OPERATION __ITS 3.1_.1,_
A2 ITS 3.1.2,I and 3.1.1.1 The SHUTDOWN MARGIN shall be_> I%Akk. dITS3.1.9 APPLICABILITY: MODES 1, *, 3 4 and . within 15 minutes L03
[ ITSSee3.1.1 ACTION: uAO rods groups inserted in Regulating -
unacceptable operation region L04 Required With the SHUTDOWN ARGIN < 1%/ A m atl initiate L d o'tineboration Action I.1 jat > 25 gpmbX7875 ppm boron oNts equivalen% until the required SHUTDOWN MARGIN is restored.
COLR L0 within limits specified in the SURVEILLANCE REQUIREMENTS SR 3.2.1.3 4.1.1.1.1 The SHUTDOWN MARGIN shall be determined to be>l* J See rod(s) andIaleast once3 _ ITS 3.1.4
- a. Within one hour after detection of an inoperable contr]
Der 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> thereafter while the rod(s) is inoprble [er-control rdSee is immovable or untrippable, the above required SHUTDOWN MARGIN shall be ITS 1.e0 increased by an amount at least equal to the withdrawn worth of the immovable o untrippable control rod(s). M0 SR 3.2.1.1, b. When in MODES I or *, at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, by verifying that regulating SR 3.2.1.2 rod groups withdrawal is within the limits of Specification 3.1.3.6. L05 SR 3.2.1.3 c. When inODE 2 within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> prior to achieving reactor criticalit byLA0 verifying that e predicted critical contro ro siti s within e imits of Specification .1.3.6.
- d. Prior to initial operation above 5% RATED THERMAL POWER after each fuel loading by consideration of the factors of e. below, with the regulating rod groups at the maximum insertion limit of Specification 3.1.3.6.
I DAVIS-BESSE, UNIT 1 3/4 1-1 Amendment No. 19tr-t92- 276 Page 3 of 3 Attachment 1, Volume 7, Rev. 0, Page 7 of 132
Attachment 1, Volume 7, Rev. 0, Page 8 of 132 DISCUSSION OF CHANGES ITS 3.2.1, REGULATING ROD INSERTION LIMITS ADMINISTRATIVE CHANGES A01 In the conversion of the Davis-Besse 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-1430, Rev. 3.1, "Standard Technical Specifications-Babcock and Wilcox Plants" (ISTS).
These changes are designated as administrative changes and are acceptable because they do not result in technical changes to the CTS.
A02 The Applicability of CTS 3.1.3.6 is MODES 1 and 2 with footnote
- stating "See Special Test Exception 3.10.1 and 3.10.2." The Applicability of CTS 3.1.1.1 includes MODE 1 and MODE 2, however MODE 2 footnote
- states "See Special Test Exception 3.10.4." ITS 3.2.1 Applicability does not contain the footnote or a reference to any Special Test Exception.
The purpose of the footnote references is to alert the user that a Special Test Exception exists that may modify the Applicability of the Specification. It is an ITS convention to not include these types of footnotes or cross-references. This change is designated as administrative as it incorporates an ITS convention with no technical change to the CTS.
MORE RESTRICTIVE CHANGES M01 CTS 3.1.3.6 requires the regulating rod groups to be positioned within acceptable limits during operations in MODES 1 and MODE 2 with keff > 1.0. CTS 3.1.1.1 requires SHUTDOWN MARGIN to be met in MODES 1 and MODE 2 however CTS 4.1.1.1.1.b only requires a verification that SHUTDOWN MARGIN is within limits by verifying that regulating rod groups withdrawal is within limits in MODE 1 and MODE 2 with keff > 1.0. ITS 3.2.1 requires the regulating rod insertion limits to apply at all times in MODES 1 and 2 and ITS SR 3.2.1.1 and SR 3.2.1.2 require verification in these modes. This changes the CTS by expanding the applicability of the regulating rod groups and requires verification to include MODE 2 with keff < 1.0.
The purpose of the CTS 3.1.3.6 is to ensure the regulating rod groups are at the acceptable operating limits to help ensure SHUTDOWN MARGIN is met.
CTS 3.1.3.6 and CTS 3.1.1.1.1 help to ensure SHUTDOWN MARGIN is met in MODES 1 and 2; however, there is no specific requirement to verify SHUTDOWN MARGIN at a consistent frequency when in MODE 2 with keff < 1.0 except the requirement in CTS 4.1.1.1.1.c (ITS SR 3.2.1.3). This change is acceptable because the ITS requires the regulating rod insertion limits to apply at all times in MODES 1 and 2 to help ensure SHUTDOWN MARGIN is maintained.
This change is designated as more restrictive because it expands the conditions for regulating rod groups and expands the conditions under which a Surveillance must be performed.
Davis-Besse Page 1 of 7 Attachment 1, Volume 7, Rev. 0, Page 8 of 132
Attachment 1, Volume 7, Rev. 0, Page 9 of 132 DISCUSSION OF CHANGES ITS 3.2.1, REGULATING ROD INSERTION LIMITS RELOCATED SPECIFICATIONS None REMOVED DETAIL CHANGES LA01 (Type 5 - Removal of Cycle-Specific ParameterLimits from the Technical Specifications to the Core OperatingLimits Report) CTS 4.1.1.1 requires that the SDM be > 1% Ak/k. ITS 3.2.1.3 states that the SDM shall be within the limits of the COLR. This changes the CTS by relocating the SDM limit, which must be confirmed on a cycle-specific basis, to the COLR.
The removal of these cycle-specific parameter limits from the Technical Specifications to the COLR is acceptable because the cycle-specific limits are developed or utilized under NRC-approved methodologies which will ensure that the Safety Limits are met. The NRC documented in Generic Letter 88-16, "Removal of Cycle-Specific Parameter Limits From Technical Specifications,"
that 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 SDM requirement. The methodologies used to develop the parameters in the COLR have obtained prior approval by the NRC in accordance with Generic Letter 88-16. Also, this change is acceptable because the removed information will be adequately controlled in the COLR under the requirements provided in ITS 5.6.3, "CORE OPERATING LIMITS REPORT." ITS 5.6.3 ensures that the applicable limits (e.g., fuel thermal mechanical limits, core thermal hydraulic limits, Emergency Core Cooling Systems limits, and nuclear limits such as SDM, transient analysis limits, and accident analysis limits) of the safety analyses are met. This change is designated as a less restrictive removal of detail change because information relating to cycle-specific parameter limits is being removed from the Technical Specifications.
LA02 (Type 3 - Removing ProceduralDetails for Meeting TS Requirements or Reporting Requirements) CTS 4.1.1.1.1.c requires verification that SHUTDOWN MARGIN is within limit by verifying the "predicted critical control rod position is within the limits" of Specification 3.1.3.6. ITS SR 3.2.1.3 requires verification that SDM is within the limits. This changes the CTS by removing details of how to perform the SHUTDOWN MARGIN verification to the Bases.
The removal of these details for performing a Surveillance Requirement from the Technical Specifications 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 verify SDM is within the limit. 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 Specification 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 procedural details for meeting Technical Specification requirements are being removed from the Technical Specifications.
Davis-Besse Page 2 of 7 Attachment 1, Volume 7, Rev. 0, Page 9 of 132
Attachment 1, Volume 7, Rev. 0, Page 10 of 132 DISCUSSION OF CHANGES ITS 3.2.1, REGULATING ROD INSERTION LIMITS LESS RESTRICTIVE CHANGES L01 (Category3 - Relaxation of Completion Time) The CTS 3.1.3.6 Action requires entry with the regulating rod groups inserted beyond the operating limits (in a region other than acceptable operation) or with any group sequence or overlap outside the limits. CTS 3.1.3.6 provides three optional Required Actions.
CTS 3.1.3.6 Action a requires restoration of the regulating groups to within the limits within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. CTS 3.1.3.6 Action b requires the reduction in THERMAL POWER to less than or equal to that fraction of RATED THERMAL POWER which is allowed by the rod group position limits. CTS 3.1.3.6 Action c requires the plant to be in Hot Standby (MODE 3) within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. ITS 3.2.1 ACTION A requires entry when regulating rod groups are inserted in the restricted operational region. ITS 3.2.1 ACTION C requires entry when regulating rod groups sequence or overlap limits are not met. ITS 3.2.1 ACTION D requires entry when regulating rod groups are inserted in the unacceptable operational region. ITS 3.2.1 ACTION A requires the performance of ITS SR 3.2.5.1 once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> when THERMAL POWER is > 20% RTP and the restoration of regulating rod groups to within limits within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from discovery of failure to meet the LCO. ITS 3.2.1 ACTION B covers the conditions when the Required Actions and associated Completion Times of Condition A are not met when the plant is operating in the restricted operational region and it allows 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> to reduce THERMAL POWER to less than or equal to THERMAL POWER allowed by regulating rod group insertion limits. ITS 3.2.1 ACTION C requires performance of ITS SR 3.2.5.1 within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> when THERMAL POWER is
> 20% RTP and the restoration of regulating rod groups to within limits within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. ITS 3.2.1 ACTION D, in part, requires the restoration of the rod groups to within restricted operating region within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> or a reduction of THERMAL POWER to less than or equal to the THERMAL POWER allowed by the regulating rod group insertion limits. This changes the CTS by extending the Completion Time to restore regulating rod groups to within limits from 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> when regulating rod groups are inserted in restricted operational region, and from 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> when regulating rod groups are not within the sequence or overlap limits. However it provides an additional requirement to verify FQ and F*H are within their limits once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> (for ITS 3.2.1 ACTION A) or within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> (for ITS 3.2.1 ACTION C) during the extended Completion Times. This change also provides an additional allowance to operate in the restricted operational region for an additional 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> (after the 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period) to reduce THERMAL POWER to less than or equal to THERMAL POWER allowed by regulating rod group insertion limits.
The purpose of the CTS 3.1.3.6 Actions are to preclude long term depletion with abnormal group insertions or configurations, thereby limiting the potential for an adverse xenon redistribution. 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. This includes the capacity and capability of remaining systems or features, a reasonable time for repairs or replacement, and the low probability of a DBA occurring during the allowed Completion Time. The CTS is changed in several ways. The Completion Time to restore regulating rod groups to within limits has been extended from 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> when regulating rod groups are inserted Davis-Besse Page 3 of 7 Attachment 1, Volume 7, Rev. 0, Page 10 of 132
Attachment 1, Volume 7, Rev. 0, Page 11 of 132 DISCUSSION OF CHANGES ITS 3.2.1, REGULATING ROD INSERTION LIMITS in restricted operational region and from 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> when regulating rod groups are not within the sequence or overlap limits. However during the time an additional requirement to verify Fa and FAH are within their limits once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> (for ITS 3.2.1 ACTION A) and within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> (for ITS 3.2.1 ACTION C) is required. This change also provides an additional allowance to operate in the restricted operational region for an additional 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> (after the 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period) to reduce THERMAL POWER to less than or equal to THERMAL POWER allowed by regulating rod group insertion limits. Operation with the regulating rods in the restricted region or with any group sequence or overlap outside the limits potentially violates the LOCA LHR limits (F0 limits), or the loss of flow accident DNB peaking limits (F.H limits). Verification that F" and F.H are within their limits ensures that operation with the regulating rods inserted into the restricted region does not violate the ECCS or DNB criteria. The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is acceptable in that it allows the operator sufficient time for obtaining a power distribution map and for verifying the power peaking factors. Repeating SR 3.2.5.1 every 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for ITS 3.2.1 ACTION A is acceptable because it ensures that continued verification of the power peaking factors is performed as core conditions (primarily regulating rod insertion and induced xenon redistribution) change. SR 3.2.5.1 is only required when THERMAL POWER is greater than 20% RTP. This establishes a Required Action that is consistent with the Applicability of LCO 3.2.5, "Power Peaking Factors." Indefinite operation with the regulating rods inserted in the restricted region, or in violation of the group sequence or overlap limits, is not prudent.
Even if power peaking monitoring is continued, reactivity limits may not be met and the abnormal regulating rod insertion or group configuration may cause an adverse xenon redistribution, may cause the limits on AXIAL POWER IMBALANCE to be exceeded, or may adversely affect the long term fuel depletion pattern. Therefore, power peaking monitoring is allowed for up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after discovery of failure to meet the LCO for ITS 3.2.1 ACTION A and only up to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> for ITS 3.2.1 ACTION C. This required Completion Time 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after discovery of failure to meet the LCO (for ITS 3.2.1 ACTION A) and 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> (for ITS 3.2.1 ACTION C) is reasonable based on the low probability of an event occurring simultaneously with the limit out of specification in this relatively short time period. Ifthe regulating rods cannot be restored within the insertion limits, then the insertion limits can be restored by reducing the THERMAL POWER to a value allowed by the regulating rod insertion limits. The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is sufficient to allow the operator to complete the power reduction in an orderly manner and without challenging the plant systems. Operation for up to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> more in the restricted region is acceptable, based on the low probability of an event occurring simultaneously with the limit out of specification in this relatively short time period. In addition, it precludes long term depletion with abnormal group insertions or configurations and limits the potential for an adverse xenon redistribution. If the regulating rods cannot be restored to within the insertion limits as required by ITS 3.2.1 ACTIONS A and C, or if the power reduction cannot be completed within the required Completion Time as required by ITS 3.2.1 ACTION B, then the reactor is placed in MODE 3, in which this LCO does not apply. This change is designated as less restrictive because additional time is allowed to restore parameters to within the LCO limits than was allowed in the CTS.
Davis-Besse Page 4 of 7 Attachment 1, Volume 7, Rev. 0, Page 11 of 132
Attachment 1, Volume 7, Rev. 0, Page 12 of 132 DISCUSSION OF CHANGES ITS 3.2.1, REGULATING ROD INSERTION LIMITS L02 (Category 7- Relaxation of Surveillance Frequency - Non-24 Month Type Change) CTS 4.1.3.6 requires the position of each regulating group to be determined to be within the limits provided in the COLR at least once every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> except during time intervals when the regulating rod insertion limit alarm or the control rod drive sequence alarm is inoperable. With either of these alarms inoperable, CTS 4.1.3.6.a requires a verification that the rod groups are within the insertion limits at least once per 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> and CTS 4.1.3.6.b requires a verification that the rod groups are within the sequence or overlap limits at least once per 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, respectively. ITS SR 3.2.1.1 requires verification that regulating rod groups are within the sequence and overlap limits of the COLR every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, and ITS SR 3.2.1.2 requires verification that the regulating rod groups meet 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 eliminating the requirement to verify that each regulating group is within insertion limits at accelerated frequencies when the regulating rod insertion limit alarm or the control rod drive sequence alarm is inoperable.
The purpose of CTS 4.1.3.6 is to periodically verify that the regulating rods are within the limits specified in the LCO. This change is acceptable because increasing the Frequency of regulating rod insertion limit verification when the regulating rod insertion limit alarm or the control rod drive sequence alarm is inoperable is unnecessary. An inoperability of the alarm does not increase the probability that the regulating rod insertion limits are not met. The routine 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Frequencies (ITS SR 3.2.1.1 and SR 3.2.1.2) continue to ensure the regulating rod limits are met. Furthermore, the regulating rod insertion limit alarm and the control rod drive sequence alarm are for indication only. Their use is not credited in any safety analyses. Thus, any response determined necessary by plant personnel due to an inoperable alarm 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 the ITS than under the CTS.
L03 (Category 3 - Relaxation of Completion Time) CTS 3.1.3.6 Action Note requires entry into the Actions of CTS 3.1.1.1 if the plant is in the unacceptable region specified in the COLR. The CTS 3.1.1.1 Action states that when the SHUTDOWN MARGIN is less than the applicable limit, boration must be initiated immediately. Under the same conditions in the ITS, ITS 3.2.1 Required Action D.1 states that boration must be initiated within 15 minutes. This changes the CTS by relaxing the Completion Time from "immediately" to 15 minutes.
The purpose of CTS 3.1.1.1 Action is to restore the SDM to within its limit promptly. This change is acceptable because the Completion Time is consistent with safe operation under the specified Condition, considering a reasonable time for restoration and the low probability of a DBA occurring during the allowed Completion Time. The ITS 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 state that boration must be initiated promptly. This change is designated as less restrictive because additional time is allowed to restore parameters to within the LCO limits than was allowed in the CTS.
Davis-Besse Page 5 of 7 Attachment 1, Volume 7, Rev. 0, Page 12 of 132
Attachment 1, Volume 7, Rev. 0, Page 13 of 132 DISCUSSION OF CHANGES ITS 3.2.1, REGULATING ROD INSERTION LIMITS L04 (Category 4 - Relaxation of Required Action) CTS 3.1.1.1 Action states that when the SDM is not within the applicable limits, boration must be initiated and continued at >- 25 gpm of a solution containing --7875 ppm boron or its equivalent until the required SDM is restored. ITS 3.2.1 Required Action D.1 states that with the regulating rod groups inserted in the unacceptable operational region to initiate boration to restore SDM to within limits. This changes the CTS by eliminating the specific values of flow rate and boron concentration that must be used to restore compliance with the LCO.
The purpose of the CTS 3.1.1.1 Action is to restore the SDM to within its limits.
This change is acceptable because the 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 time to repair inoperable features. 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. Removing the specific values of flow rate and boron concentration from the CTS Action provides flexibility in the restoration of the SDM and eliminates conflicts between the SDM value and the specific boration values in the CTS Action. As stated in the ITS 3.1.1 Bases for ACTION A, "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." Specifying a minimum flow rate and concentration in the ACTION may not accomplish the objective of raising the RCS boron concentration as soon as possible. This change is designated as less restrictive because less stringent Required Actions are being applied in the ITS than were applied in the CTS.
L05 (Category 7- Relaxation Of Surveillance Frequency - Non-24 Month Type Change) CTS 4.1.1.1.1 .c requires verification of SDM, when in MODE 2 with ke,
< 1.0, within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> prior to achieving reactor criticality. ITS SR 3.2.1.3 requires SDM to be verified within limit 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. This changes the CTS by eliminating the explicit statement that the Surveillance is required to be performed in MODE 2.
The purpose of CTS 4.1.1.1.1 .c is to estimate the critical position of the control rods 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> prior to going critical. This change is acceptable because the proposed Surveillance Frequency of 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 ensures that there is sufficient SDM capability with the control rods at the estimated critical position. CTS 4.1.1.1.1 .c requires verification of SDM, when in MODE 2 with kef < 1.0, within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> prior to achieving reactor criticality. ITS SR 3.2.1.3 requires SDM to be within limit 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. This change eliminates the explicit statement that the Surveillance is required to be performed in MODE 2. The Surveillance may be performed in another MODE as long as it is performed within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> of going critical. The Surveillance Frequency still requires the estimated critical position to be Davis-Besse Page 6 of 7 Attachment 1, Volume 7, Rev. 0, Page 13 of 132
Attachment 1, Volume 7, Rev. 0, Page 14 of 132 DISCUSSION OF CHANGES ITS 3.2.1, REGULATING ROD INSERTION LIMITS determined within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> prior to criticality and is therefore acceptable because it provides sufficient time to establish the estimated critical position after the determination is performed. This change is designated as less restrictive because the Surveillance is not required to be performed in MODE 2.
Davis-Besse Page 7 of 7 Attachment 1, Volume 7, Rev. 0, Page 14 of 132
Attachment 1, Volume 7, Rev. 0, Page 15 of 132 Improved Standard Technical Specifications (ISTS) Markup and Justification for Deviations (JFDs)
Attachment 1, Volume 7, Rev. 0, Page 15 of 132
Attachment 1, Volume 7, Rev. 0, Page 16 of 132 Regulating Rod Insertion Limits
.3.2.1 CTS 3.2 POWER DISTRIBUTION LIMITS 3.2.1 Regulating Rod Insertion Limits 3.1.3.6 LCO 3.2.1 Regulating rod groups shall be Within the physical insertion, sequence, and overlap limits specified in the COLR.
NOTE-----------------------
3.1.3.6 Not required for any regulating rod repositioned to perform SR 3.1.4.2.
Action APPLICABILITY: MODES 1 and 2.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME 3.1.3.6 A. Regulating rod groups A.1 ---------- NOTE-------
Action a inserted in restricted Only required when operationE region, or THERMAL POWER is sequencq or over ap, or > 20% RTP.
[any comb. ation, not - 0 metý Perform SR 3.2.5.1. Once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> AND A.2 Restore regulating rod 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from groups to within limits, discovery of failure to meet the LCO B. Required Action and B.1 Reduce THERMAL 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> 3.1.3.6 Action b associated Completion POWER to less than or Time of Condition A not equal to THERMAL met. POWER allowed by regulating rod group insertion limits.
INSERT1 0 BVWOG STS 3.2.1-1 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 16 of 132
Attachment 1, Volume 7, Rev. 0, Page 17 of 132 3.2.1 CTS (3INSERT I 3.1.3.6 C. Regulating rod groups C.1 --------- NOTE--------
Action a sequence or overlap Only required when limits not met. THERMAL POWER is
> 20% RTP.
Perform SR 3.2.5.1. 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> AND C.2 Restore regulating rod groups 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> to within limits.
Insert Page 3.2.1-1 Attachment 1, Volume 7, Rev. 0, Page 17 of 132
Attachment 1, Volume 7, Rev. 0, Page 18 of 132 Regulating Rod Insertion Limits 3.2.1 0 CTS ACTIONS (continued)
CON DITION REQU IRED ACTION COMPLETION TIME 3.1.3.6 Action
( Regulating rod groups inserted in unacceptable 1 Initiateboration to restore SDM to within the limit 15 minutes 0
Note. operationg region. Ispecifiedcl'fthe COLR].
3.1.1.1 Action AND 2.1 Restore regulating rod 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> Sgroups to within restricted operatrgreion.
OR 912.2 Reduce THERMAL POWER to less than or 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> 0 equal to the THERMAL Fthe resticted operation region of POWER allowed by'the regulating rod group insertion limits.
3.1.3.6 I Required Action and [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 /> Action associated Completion
}
Note, 3.1.1.1 Time of Condition C ot Action met. o SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY 4.1.3.6, Verify regulating rod groups are within the sequence 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> 4.1.1.1.1.b SR 3.2.1.1 and overlap limits as specified in the COLR.
4.1.3.6, SR 3.2.1.2 Verify regulating rod groups meet the insertion limits 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> 4.1.1.1.1.b as specified in the COLR.
4.1.1.1.1.c SR 3.2.1.3 Verify SDM is within the limit 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 BWOG STS 3.2.1-2 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 18 of 132
Attachment 1, Volume 7, Rev. 0, Page 19 of 132 JUSTIFICATION FOR DEVIATIONS ITS 3.2.1, REGULATING ROD INSERTION LIMITS
- 1. If the regulating rod groups are not within the sequence or overlap limits, ISTS 3.2.1 ACTION A allows up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to restore the regulating rod groups to within the limits. This is an excessive time to allow the unit to operate outside these limits.
Therefore, ITS ACTION C has been added to only allow 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> to restore the regulating rod groups to within the sequence and overlap limits. This is consistent with the Arkansas Nuclear One (ANO) ITS amendment, as approved by the NRC on October 29, 2001. Furthermore, consistent with ISTS 3.2.1 Required Action A.1, performance of SR 3.2.5.1 is required within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. Further performance of the SR (i.e., every 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />) is not required since the rods have to be restored within the limits by the time the next performance would be required. Due to this change, ISTS 3.2.1 Condition A has been modified to delete sequence and overlap references, and subsequent ACTIONS have been renumbered.
- 2. Changes are made to be consistent with the format of the ITS. The location of where a parameter's limits reside, whether in the COLR or an actual LCO statement, is not normally specified in the Required Action. The Required Action normally states that the parameter shall be "within limits."
- 3. Clarifying words have been added. Power only has to be reduced to exit the unacceptable operation region.
Davis-Besse Page 1 of 1 Attachment 1, Volume 7, Rev. 0, Page 19 of 132
Attachment 1, Volume 7, Rev. 0, Page 20 of 132 Improved Standard Technical Specifications (ISTS) Bases Markup and Justification for Deviations (JFDs)
Attachment 1, Volume 7, Rev. 0, Page 20 of 132
Attachment 1, Volume 7, Rev. 0, Page 21 of 132 Regulating Rod Insertion Limits B 3.2.1 B 3.2 POWER DISTRIBUTION LIMITS B 3.2.1 Regulating Rod Insertion Limits BASES BACKGROUND The insertion limits of the regulating rods are initial condition assumptions used in all safety analyses that assume rod insertion upon reactor trip.
The insertion limits directly affect the core power distributions, the worth of a potential ejected rod, the assumptions of available SDM, and the initial reactivity insertion rate..
distribution design criteria for these reactivity and power wThe applicable Design, i GDC-26, "Reactivity, t
- Control System Redunoancy-a~n~d Cpbility " GDC 28, 'Reacti tity ILimits" t(Ref. 1), and in 10 CFR 50.46, "Acceptance Criteria for Emergency Core Cooling Systems for Light Water Nuclear Power Plants" (Ref. 2).
1 are specified in the COLR Limits on regulating rod insertionf have beern stablishedk 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 not violated.
The regulating rod groups operate with a predetermined amount of position overlap, in-or-er-to approximate a linear relation between rod Q worth and rod position (integral rod worth). To achieve this approximately linear relationship, the regulating rod groups are withdrawn and operated in a predetermined sequence. The automatic control system controls reactivity by moving the regulating rod groups in sequence within analyzed ranges. The group sequence and overlap limits are specified in the COLR.
The regulating rods are used for precise reactivity control of the reactor.
The positions of the regulating rods are normally controlled automatically by the automatic control system but can also be controlled manually.
They are capable of adding reactivity quickly compared with borating or diluting the Reactor Coolant System (RCS).
The power density at any point in the core must be limited to maintain specified acceptable fuel design limits, including limits that ensure that the criteria specified in 10 CFR 50.46 (Ref. 2) are not violated. Together, LCO 3.2.1, "Regulating Rod Insertion Limits," LCO 3.2.2, "AXIAL POWER SHAPING ROD (APSR) Insertion Limits," LCO 3.2.3, "AXIAL POWER BWOG STS B 3.2.1-1 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 21 of 132
Attachment 1, Volume 7, Rev. 0, Page 22 of 132 B 3.2.1 O) INSERT 1 UFSAR, Appendices 3D.1.6, 3D.1.21, 3D.1.22, 3D.1.23, and 3D.1.24 Insert Page B 3.2.1-1 Attachment 1, Volume 7, Rev. 0, Page 22 of 132
Attachment 1, Volume 7, Rev. 0, Page 23 of 132 Regulating Rod Insertion Limits B 3.2.1 BASES BACKGROUND -(continued)
IMBALANCE Operating Limits," and LCO 3.2.4, "QUADRANT POWER TILT (QPT)," provide limits on control component operation and on monitored process variables to ensure that the core operates within the
.FQMI )and FH,, limits in the COLR. Operation within the FQM-) limits given in the COLR prevents power peaks that would exceed the loss of coolant 0
linear heat rate (LHR) accident (LOCA) limits derived from the analysis of the Emergency Core Cooling Systems (ECCS). Operation within the FA.H limits given in the 0
.COLR prevents departure from nucleate boiling (DNB) during a loss of forced reactor coolant flow accident. In addition to the Fa 2) and F&-H limits, certain reactivity limits are met by regulating rod insertion limits.
0 The regulating rod insertion limits also restrict the ejected CONTROL ROD worth to the values assumed in the safety analysis and maintain the minimum required SDM in MODES 1 and 2.
This LCO is required to minimize fuel cladding failures that breach the primary fission product barrier and release fission products into the reactor coolant in the event of a LOCA, loss of flow accident, ejected rod accident, or other postulated accidents requiring termination by a Reactor Protection System trip function.
APPLICABLE The fuel cladding must not sustain damage as a result of normal SAFETY operation (Condition 1) or anticipated operational occurrences ANALYSES (Condition 2). The LCOs governing regulating rod insertion, APSR position, AXIAL POWER IMBALANCE, and QPT preclude core power distributions that violate the following fuel design criteria:
- a. During a a exceed 2200°F (Ref. 2).
LOCA, the peak cladding temperature must not 01
- b. During a loss of forced reactor coolant flow accident, there must be at least 95% probability at the 95% confidence level (the 95/95 DNB criterion) that the hot fuel rod in the core does not experience a DNB condition (Ref. I o 00
- c. During an ejected rod accident, the fission energy input to the fuel must not exceed 280 cal/gm (Ref. _
00
- d. The CONTROL RODS must be capable of shutting down the reactor with a minimum required SDM with the highest worth CONTROL ROD stuck fully withdrawn (Ref. 1).
BWVOG STS B 3.2.1-2 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 23 of 132
Attachment 1, Volume 7, Rev. 0, Page 24 of 132 Regulating Rod Insertion Limits B 3.2.1 BASES APPLICABLE SAFETY ANALYSES (continued)
Fuel cladding damage does not occur when the core is operated outside the conditions of these LCOs during normal operation. However, fuel cladding damage could result if an accident occurs with the simultaneous violation of one or more of the LCOs limiting the regulating rod position, the APSR position, the AXIAL POWER IMBALANCE, and the QPT. This potential for fuel cladding damage exists because changes in the power distribution can cause increased power peaking and correspondingly increased local Ilinear-lie-6t rates ELHRsý The SDM requirement is met by limiting the regulating and safety rod insertion limits such that sufficient inserted reactivity is available in the rods to shut down the reactor to hot zero power with a reactivity margin that assumes that the maximum worth rod remains fully withdrawn upon trip (Ref. 4). Operation at the SDM based regulating rod insertion limit may also indicate that the maximum ejected rod worth could be equal to the limiting value.
Fbeyondý Operati-onthe regulating rod insertion limits may cause the local core Q power to approach the maximum linear heat generation rate or peaking factor with the allowed QPT present.
The regulating rod and safety rod insertion limits ensure that the safety analysis assumptions for SDM, ejected rod worth, and power distribution peaking factors remain valid (Refs.[3, 5, and n 6.5 a The regulating rod insertion limits LCO satisfies Criterion 2 of 10 CFR 50.36(c)(2)(ii).
LCO regurng e limits on CONTR'QL ROD sequence, including group overlap, and insertion positions as defined in the COLR, must be maintained because they ensure that the resulting power distribution is within the range of analyzed power distributions and that the SDM and ejected rod worth are maintained.
The overlap between regulating groups provides more uniform rates of reactivity insertion and withdrawal and is imposed to maintain acceptable power peaking during regulating rod motion.
Error m-a-mum -aiwablesepointslfor regulating rod insertion limits Q are provided in the COLR. The setpoinqtslre derived by an adjustment of the measurement system independent limits to allow for THERMAL POWER level uncertainty and rod position errors.
BVWOG STS B 3.2.1-3 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 24 of 132
Attachment 1, Volume 7, Rev. 0, Page 25 of 132 Regulating Rod Insertion Limits
-B 3.2.1 BASES LCO (continued)
Actual - arm setpoints impl ented in the unit rnay\,e more restrictive than the., .aximum allowable etpdintvalues to provkie additional conservatism between the act.,al alarm setpoint and the measurement system independent limit.
LCO 3.2.1 has been modified by a Note that suspends the LCO requirement for those regulating rods not within the limits of the COLR solely due to testing in accordance with SR 3.1.4.2, which verifies the freedom of the rods to move. This SR may require the regulating rods to move below the LCO limit, which would otherwise violate the LCO.
APPLICABILITY The regulating rod sequence, overlap, and physical insertion limits shall be maintained with the reactor in MODES 1 and 2. These limits maintain the validity of the assumed power distribution, ejected rod worth, SDM, and reactivity insertion rate assumptions used in the safety analyses.
Applicability in MODES 3, 4, and 5 is not required, because neither the power distribution nor ejected rod worth assumptions are exceeded in these MODES. SDM in MODES 3, 4, and 5 is governed by LCO 3.1.1, "SHUTDOWN MARGIN (SDM)."
ACTIONS The regulating rod insertion jalarm Ktpoints provided in the COLR are 0 based on both the initial conditions assumed in the accident analyses and on the SDM. Specifically, separate insertion limits are specified to determine whether the unit is operating in violation of the initial conditions (e.g., the range of power distributions) assumed in the accident analyses or whether the unit is in violation of the SDM or ejected rod worth limits.
Separate insertion limits are provided because different Required Actions and Completion Times apply, depending on which insertion limit has been violated. The area between the boundaries of acceptable operation and unacceptable operation, illustrated on the regulating rod insertion limit figures in the COLR, is the restricted region. The actions required when operation occurs in the restricted region are described under Condition A.
The actions required when operation occurs in the unacceptable region are described under Condition1 0 are dThe actions required when operation occurs with L -- the regulating rod group sequence or overlap limits A.1 not met are described under Condition C.
Operation with the regulating rods in the restricted region shown on the regulating rod insertion figures specified in the COLR or viitn any group Isequence or ovrlap outside the Iinlits speci ed in the CCLR potentially 00
©©{90 violates the LOCA LHR limits (Fo M) limits), or the loss of flow accident DNB peaking limits F,' limits). 'he design caructions assume no 7f BWAOG STS B 3.2.1-4 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 25 of 132
Attachment 1, Volume 7, Rev. 0, Page 26 of 132 Regulating Rod Insertion Limits B 3.2.1 BASES ACTIONS (continued) deviation in nominral overlap between regulating rod groups. However.,
deviations of 5% oi~the core height above or \elow the nominal overlap may be typical and o not cause significant .dierences in core reactivity, in power distribIutionIor in rod worth, relative tc.*the design calculations.
The group sequence \'nust be maintained becar~se design calculations assume the regulating rods withdraw and insert \n a predetermined order.
For verification that FQ') and F',H are within their limits, SR 3.2.5.1 is performed using the Incore Detector Systemto obtain a three dimensional power distribution map. Verification that FQ -2)andFA , are 0 within into thetheir limits ensures that operation with the regulating rods inserted restricted.region does not violate the ECCS or DNB criteria 6 (Ref. Z). The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is acceptable in that it allows the operator sufficient time for obtaining a power distribution map and for verifying the power peaking factors. Repeating SR 3.2.5.1 every 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is acceptable because it ensures that continued verification of the power peaking factors is performed as core conditions (primarily regulating rod insertion and induced xenon redistribution) change.
Monitoring the power peaking factors FQ 0 )and FA H does not provide verification that the reactivity insertion rate on the rod trip or the ejected rod worth limit is maintained, because worth is a reactivity parameter rather than a power peaking parameter. However, if the COLR figures do not show that a rod insertion limit is ejected rod worth limited, then the ejected rod worth is no more limiting than the SDM based rod insertion
[D limit in the core design (Ref.*j. Ejected rod worth limits are (7) independently maintained by the Required Actions of Conditions A and Required Action A.1 is modified by a Note that requires the performance of SR 3.2.5.1 only when THERMAL POWER is greater than 20% RTP.
This establishes a Required Action that is consistent with the Applicability of LCO 3.2.5, "Power Peaking Factors."
A.2 Indefinite operation with the regulating rods inserted in the restricted regioný or in violation f the group sequ , ce or overlap limits,lis not 0 prudent. Even if power peaking monitoring per Required Action A.1 is continued, reactivity limits may not be met and the abnormal regulating rod insertion or group configuration may cause an adverse xenon redistribution, may cause the limits on AXIAL POWER IMBALANCE to be exceeded, or may adversely affect the long term fuel depletion pattern.
BWAOG STS B 3.2.1-5 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 26 of 132
Attachment 1, Volume 7, Rev. 0, Page 27 of 132 Regulating Rod Insertion Limits B 3.2.1 BASES ACTIONS (continued) restoration of the regulating rod groups to within limits is required within Therefore, power pea" monitoring i~llowed for up toJ24 hours after 0 discovery of failure to meet the requirements of this .LCO. This required Completion Time is reasonable :based on the low.probability of an event occurring simultaneously with the limit out of specification :in this relatively short time period. In addition, it precludes long term depletion with abnormal group insertions or configurations, thereby limiting the potential for an adverse xenon redistribution.
B.1 ( operation region If the regulating rods cannot be restored within the acceptable e ýtin in]Tsshown on the figures in the COLR within the required Completion Time .(i.e., Required Action A.2 not met), then the limit.can be restored by reducing the THERMAL POWER to a value allowed by the regulating rod insertion limits in the COLR. The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is sufficient to allowthe operator to complete the power reduction in an orderly manner and without challenging the plant systems.
Operation for up to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> more in the restricted region shown in thepeo )
COLR is acceptable, based on the low probability of an event occurring Jsimultaneously with the~limit out of specification in this relatively short time period. In addition, it precludes long term depletion with abnormal group .insertions or configurations and limits the potential for an adverse xenon redistribution.
0 Operation in the unacceptableregion shown on the figures in the COLR corresponds to power operation with an SDM less than the minimum required value or with the ejected rod worth greater than the allowable value. The regulating rods may be inserted too far to provide sufficient negative reactivity insertion following a reactor trip and the ejected rod worth may exceed its initial condition limit. Therefore, the RCS boron concentration must be increased to restore the regulating rod insertion to a value that preserves the SDM and ejected rod worth limits. The RCS theBases(of boration must occur as described in e 0 . .he required LCO3.i. K Completion Time of 15 minutes to initiate boration is reasonable, based on limiting the potential xenon redistribution, the low probability of an BWOG STS B 3.2.1-6 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 27 of 132
Attachment 1, Volume 7, Rev. 0, Page 28 of 132 B 3.2.1 O INSERT 2 C.1 and C.2 Operation with the regulating rod groups out of sequence or with the group overlap limits exceeded may represent a condition beyond the assumptions used in the safety analyses, including SDM. The design calculations assume no deviation in nominal overlap between regulating rod groups. However, deviations as allowed by the COLR above or below the nominal overlap may be typical and would not cause significant differences in core reactivity, in power distribution, or in rod worth, relative to the design calculations. The group sequence must be maintained because design calculations assume the regulating rods withdraw and insert in a predetermined order.
For verification that FQ and FA H are within their limits, SR 3.2.5.1 is performed using the Incore Detector System to obtain a three dimensional power distribution map. Verification that FQ and F. H are within their limits ensures that operation with the regulating rods sequence or overlap limits not met does not violate the ECCS or DNB criteria (Ref. 6). The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is acceptable in that it allows the operator sufficient time for obtaining a power distribution map and for verifying the power peaking factors. Required Action C.1 is modified by a Note that requires the performance of SR 3.2.5.1 only when THERMAL POWER is greater than 20% RTP. This establishes a Required Action that is consistent with the Applicability of LCO 3.2.5.
Indefinite operation with the regulating rods sequence or overlap limits not met is not prudent because of the potential severity associated with gross violations of group sequence or overlap requirements. Therefore, the regulating rod groups must be restored to within the sequence and overlap limits within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. The 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> Completion Time is based on operating experience which supports the restoration time without unnecessarily challenging unit operation and the low probability of an event occurring simultaneously with the limit out of specification.
Insert Page B 3.2.1-6 Attachment 1, Volume 7, Rev. 0, Page 28 of 132
Attachment 1, Volume 7, Rev. 0, Page 29 of 132
.Regulating Rod Insertion Limits B 3.2.1 BASES ACTIONS (continued) accident occurring .in this relatively short time period, and the number of steps required to complete this Action. This period allows the operator sufficient time for aligning the required valves and for starting the boric acid pumps. Boration continues until the regulating rod group positions are restored to at least within the restricted operational region, which restores the minimum SDM capability and reduces the potential ejected rod worth to within its limit.
U-2.1 0 The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> from initial discovery of a operation regulating rod group in the unacceptableiregion until its restoration .to.
within the restricted operatir g region shown on the figures in the COLR allows sufficient time for borated water to enter the RCS from the chemical addition and makeup systems, thereby allowing the regulating unacceptable rods to be withdrawn to the restricted region. Operation in thejrest0ctedi (1 operation region for op to an-,iddiftona l2 hours is reasonable, based on limiting :the potential for an adverse xenon redistribution, the low probability of an accident occurring in this relatively short time period, and the number of steps required to complete this Action.
Ft2 .2 0
The SDM and ejected rod worth limit can also be restored by reducing the THERMAL POWER to a value allowed by the regulating rod insertion limits in the COLR. The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is sufficient to allow the operator to complete the power reduction in an orderly manner and without challenging the plant systems. Operation for up to unacceptable operation 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> m re] in therestte region shown in the COLR is acceptable, based on the Fow probability of an event occurring simultaneously with the 0 limit out of specification in this relatively short time period. In addition, it precludes long term depletion with abnormal group insertions or configurations and limits the potential for an adverse xenon redistribution.
BWOG STS B 3.2.1-7 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 29 of 132
Attachment 1, Volume 7, Rev. 0, Page 30 of 132 Regulating Rod Insertion Limits B 3.2.1 BASES ACTIONS (continued)
ýany Required Action and associated Completion LL*i 1 L Time of Condition C or D is not met Ifhe reIculating rods .cannot be/ restored to within the/acceptable
- peratin limits for the original/THERMAL POWER,/r if the power reducticn cannot be complete/ within the required' ompletion Time, then the reactor is placed in MODE 3, in which this LCO does not apply. This Action ensures that the reactor does not continue operating in violation of the peaking limits, the ejected rod worth, the reactivity insertion rate assumed as initial conditions in the accident analyses, or the required minimum SDM assumed in the accident analyses. The required 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 regarding the amount of time required to reach MODE 3 from RTP without challenging plant systems.
SURVEILLANCE SR 3.2.1.1 REQUIREMENTS This Surveillance ensures that the sequence and overlap limits are not violated. A Surveillance Frequency of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> is acceptable because 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 /> due to fuel burnup and t pro a ility (D of a deviation o,*curring simiultaneousl/y With an inoperable ý*equence monitor in this r/elatively short time fro/me is low Adso, the Frequency takes into account other information available in the control room for monitoring the status of the regulating rods.
SR 3.2.1.2 With ah.QPERABLE r ulating rod inser-i limit alarm, 'lerification of the 4 regulating rod insertion limits as specified in the COLR 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 Iro ensudre the OPER'At31LITY of the r-e.gulating rodI
'iný%eýrtion Iry it alargi and to detect regulating rod[]a*~sthat may be gro s (
approaching the group insertion limits, because ittle rod motion due to fuel burnup occurs in 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. Also, the Frequency takes into account other information available in the control room for monitoring the status of the regulating rods.
BWOG STS B 3.2.1-8 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 30 of 132
Attachment 1, Volume 7, Rev. 0, Page 31 of 132 Regulating Rod Insertion Limits B 3.2.1 BASES SURVEILLANCE REQUIREMENTS (continued)
SR 3.2.1.3 win4hours - *'riorto achieving criticality, an estimated critical position for the CONTROL RODS is determined. Verification that SDM meets the 0
minimum requirements ensures that sufficient SDM capability exists with the CONTROL RODS at the estimated critical position if it is necessary to shut down or trip the reactor after criticality. The Frequency of 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> prior to criticality provides sufficient time to verify SDM capability and establish the estimated critical position.
REFERENCES 1. ýOCFR50,Appenai-x-AGDC 10andGDC26ý 2 1C 4UFSAR Appendices 3D.1.6, 0
- 2. 10 CFR 50.46.
0 C3D.1.21, 3D.1.22. 3D.1.23, 3.PFSAR, Section [1. 15.4.3 and 3D.1.24 0
- 4. "FSAR, Section [. 15-. 0 0 5.qFSAR, Section j. 0 0 0 0 0 0 0
BWOG STS B 3.2.1-9 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 31 of 132
Attachment 1, Volume 7, Rev. 0, Page 32 of 132 JUSTIFICATION FOR DEVIATIONS ITS 3.2.1 BASES, REGULATING ROD INSERTION LIMITS
- 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. These punctuation corrections have been made consistent with the Writer's Guide for the Improved Standard Technical Specifications, TSTF-GG-05-01, Section 5.1.3.
- 3. Changes are made to reflect changes made to the Specification.
- 4. Changes are made to reflect the Specification.
- 5. The brackets have been removed and the proper plant specific information/value has been provided.
- 6. Davis-Besse was designed and under construction prior to the promulgation of 10 CFR 50, Appendix A. The design of Davis-Besse meets the intent of 10 CFR 50, Appendix A published in the Federal Register on February 20, 1971, and as amended in Federal Register on July 7, 1971. Bases references to the 10 CFR 50, Appendix A criteria have been replaced with references to the appropriate section of the UFSAR.
- 7. Editorial change corrected with no change in intent.
- 8. The ISTS 3.2.1 LCO Bases includes a discussion of "Actual Alarm Setpoints" for Regulating Rod insertion limits. This discussion is not included in the ITS LCO 3.2.1 Bases. The "Actual Alarm Setpoints" are not needed to satisfy the requirements of the LCO and therefore a discussion of the "Actual Alarm Setpoints" is not needed in the LCO Bases.
- 9. Changes are made to be consistent with other places in the Bases (i.e., LCO 3.2.5 Bases Background).
Davis-Besse Page 1 of 1 Attachment 1, Volume 7, Rev. 0, Page 32 of 132
Attachment 1, Volume 7, Rev. 0, Page 33 of 132 Specific No Significant Hazards Considerations (NSHCs)
Attachment 1, Volume 7, Rev. 0, Page 33 of 132
Attachment 1, Volume 7, Rev. 0, Page 34 of 132 DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATIONS ITS 3.2.1, REGULATING ROD INSERTION LIMITS There are no specific NSHC discussions for this Specification.
Davis-Besse Page 1 of 1 Attachment 1, Volume 7, Rev. 0, Page 34 of 132
Attachment 1, Volume 7, Rev. 0, Page 35 of 132 ATTACHMENT 2 ITS 3.2.2, AXIAL POWER SHAPING ROD (APSR) INSERTION LIMITS Attachment 1, Volume 7, Rev. 0, Page 35 of 132
, Volume 7, Rev. 0, Page 36 of 132 Current Technical Specification (CTS) Markup and Discussion of Changes (DOCs) , Volume 7, Rev. 0, Page 36 of 132
Attachment 1, Volume 7, Rev. 0, Page 37 of 132 ITS 3.2.2 ITS 0
EACTIVITY CG;'TROL SYSTEMS XIAL POWER SIIAPIN{G ROD INSERTION L1i4ITS kIMTTj.1f COQJDITInIN FOR OPERATION 3.1.3.9 The axial oower shaping rod group shall be within the acceptable LCO operating limits for axial power shaping rod position specified in the CORE 3.2.2 OPERATING LIMITS REPORT.
APPLICABILITY: MODES 1 and 2ýj MOS ACTION:
ACTION A With the axial power shaping rod group outside the above insertion limits, L01 either: Add
- a. Restore e axial power shaping rod group to within the limits within 'hours, or :L-24
- b. Red e THERMAL POWER to ess than or equal to th t fraction of RATE THERMPAL POWER whilc is allowed by the rod goup position using the acceptable oper ing limits provided in he CORE OPERATING A02 LIMITS REPORT within 2 hou . orIt rvd i u ot2P ACTION B c. Be in at least HOT STANDBY within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
SURVEILLANCE REOUIREI4ENTS SR 3.2.2.1 4.1.3.9 The position of the axial power shaping rod group shall be determined to be within the limits provided in the CORE once ever~y 12 hriours/except when the axila OPERATING power shapring LIMITS REPORT at jimit/
roo i~ertion least I the iit provided in/__! _
the group to be within alarm is inop~eb-lei then verify L0 every 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />(.m the CORE OPER iING LIMITS REPORT at least once
-W h k fý L 1.0.
Mot1 DAVIS-BESSE, UNIT 1 3/4 1-34 Amendment No. ;A,#, W01501 8*0,lf,144 (Next page is 3/4 2-1)
Page 1 of 1 Attachment 1, Volume 7, Rev. 0, Page 37 of 132
Attachment 1, Volume 7, Rev. 0, Page 38 of 132 DISCUSSION OF CHANGES ITS 3.2.2, AXIAL POWER SHAPING ROD (APSR) INSERTION LIMITS ADMINISTRATIVE CHANGES A01 In the conversion of the Davis-Besse 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-1430, Rev. 3.1, "Standard Technical Specifications-Babcock and Wilcox Plants" (ISTS).
These changes are designated as administrative changes and are acceptable because they do not result in technical changes to the CTS.
A02 In the event the APSRs are outside the operating limits specified in the CORE OPERATING LIMITS REPORT (COLR), CTS 3.1.3.9 Action b requires a reduction in THERMAL POWER to less than or equal to that fraction of RATED THERMAL POWER which is allowed by the rod group position using the acceptable operating limits provided in the COLR within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, as one of three alternative actions. ITS 3.2.2 does not provide a comparable Required Action for this Condition. This change deletes the CTS Action to reduce THERMAL POWER to less than or equal to that fraction of RATED THERMAL POWER which is allowed by the rod group position using the acceptable operating limits provided in the COLR within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, in the event that the APSRs are not within the limits provided in the COLR.
The COLR provides APSR insertion limits based on exposure. The APSR insertion limits are not based on THERMAL POWER. Therefore a reduction of the THERMAL POWER to less than or equal to that fraction of RATED THERMAL POWER which is allowed by the rod group position using the acceptable operating limits provided in the COLR is not an appropriate action.
This change is designated as administrative because it does not result in a technical change to the CTS.
MORE RESTRICTIVE CHANGES M01 The Applicability of CTS 3.1.3.9 is MODE 1 and MODE 2 with the Applicability in MODE 2 modified by a footnote, designated as "#," stating "With keff > 1.0."
ITS 3.2.2 Applicability is MODE 1 and 2. The CTS is revised to delete the footnote.
The purpose of the footnote is to provide an allowance such that, when in MODE 2 with the reactor not critical, the APSR insertion limits are not applicable.
This change provides a more restrictive requirement, in that the APSR insertion limits are now applicable at all times in MODE 2. This change is acceptable because applying that requirement prior to bringing the reactor critical ensures the APSR are in the correct position when required so that the axial fuel burnup design conditions assumed in the reload safety analyses will be satisfied. This change is designated as more restrictive because the Applicability has been broadened to encompass all of MODE 2.
Davis-Besse Page 1 of 3 Attachment 1, Volume 7, Rev. 0, Page 38 of 132
Attachment 1, Volume 7, Rev. 0, Page 39 of 132 DISCUSSION OF CHANGES ITS 3.2.2, AXIAL POWER SHAPING ROD (APSR) INSERTION LIMITS RELOCATED SPECIFICATIONS None REMOVED DETAIL CHANGES None LESS RESTRICTIVE CHANGES L01 (Category 3 - Relaxation of Completion Time) In the event the APSRs are outside the operating limits specified in the COLR, CTS 3.1.3.9 Action a requires the APSRs to be restored to within the limits within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, as one of three alternative actions. ITS 3.2.2 ACTION A provides a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Completion Time to restore the APSRs to within limits and requires the performance of SR 3.2.5.1 (Verify FQ and FNH are within limits by using the Incore Detector System to obtain a power distribution map) when THERMAL POWER is > 20% RTP once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. This changes the CTS by extending the Completion Time from "2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />" to "24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />" and provides a requirement to verify FQ and F. H are within their limits once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />.
The purpose of the CTS 3.1.3.9 Action a is to ensure that the APSRs are restored so that the axial burnup distribution that accumulates in the fuel will be consistent with the expected (as designed) distribution. This change is acceptable because the Completion Time is consistent with safe operation under the specified Condition. This change extends the Completion Time to restore APSRs to within insertion limits from "2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />" to "24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />" and provides a requirement to verify Fa and F. H are within their limits once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />.
Successful verification that Fa and FAH are within their limits ensures that operation with the APSRs inserted or withdrawn in violation of the times specified in the COLR do not violate either the ECCS or DNB criteria. The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is reasonable to allow the operator to obtain a power distribution map and to verify the power peaking factors. Repeating SR 3.2.5.1 every 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is reasonable to ensure that continued verification of the power peaking factors is obtained as core conditions (primarily the regulating rod insertion and induced xenon redistribution) change. Required Action A.1 is modified by a Note that requires the performance of SR 3.2.5.1 only when THERMAL POWER is greater than 20% RTP. This establishes a Required Action that is consistent with the Applicability of LCO 3.2.5, "Power Peaking Factors." Indefinite operation with the APSRs inserted or withdrawn in violation of the times specified in the COLR is not prudent. Even if power peaking monitoring is continued, the abnormal APSR insertion or withdrawal may cause an adverse xenon redistribution, may cause the limits on AXIAL POWER IMBALANCE to be exceeded, or may affect the long term fuel depletion pattern.
Therefore, power peaking monitoring is allowed for up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. This required Completion Time is reasonable based on the low probability of an event occurring simultaneously with the APSR limit out of specification. In addition, it Davis-Besse Page 2 of 3 Attachment 1, Volume 7, Rev. 0, Page 39 of 132
Attachment 1, Volume 7, Rev. 0, Page 40 of 132 DISCUSSION OF CHANGES ITS 3.2.2, AXIAL POWER SHAPING ROD (APSR) INSERTION LIMITS precludes long term depletion with the APSRs in positions that have not been analyzed, thereby limiting the potential for an adverse xenon redistribution. This time limit also ensures that the intended burnup distribution is maintained, and allows the operator sufficient time to reposition the APSRs to correct their positions. This change is designated as less restrictive because additional time is allowed to restore parameters to within the LCO limits than was allowed in the CTS.
L02 (Category 7- Relaxation of Surveillance Frequency - Non-24 Month Type Change) CTS 4.1.3.9 requires the position of the APSR group to be determined to be within the limits provided in the CORE OPERATING LIMITS REPORT (COLR) at least once every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> except during time intervals when the APSR insertion limit alarm is inoperable. With this alarm inoperable, CTS 4.1.3.9 requires the verification that the group is within the limit provided in the COLR at least once per 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. ITS SR 3.2.2.1 requires verification that APSRs are within the acceptable 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 eliminating the requirement to verify that the APSR group is within the limits provided in the COLR at least once per 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> when the APSR insertion limit alarm is inoperable.
The purpose of CTS 4.1.3.9 is to periodically verify that the APSRs are within the limits specified in the LCO. This change is acceptable because increasing the Frequency of APSR insertion limit verification when the APSR insertion limit alarm is inoperable is unnecessary. An inoperability of the alarm does not increase the probability that the APSR insertion limits are not met. 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 3.2.2.1) continues to ensure the APSR insertion limits are met. Furthermore, the APSR insertion limit alarm is for indication only.
Its use is not credited in any safety analyses. Thus, any response determined necessary by plant personnel due to an inoperable alarm 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 the ITS than under the CTS.
Davis-Besse Page 3 of 3 Attachment 1, Volume 7, Rev. 0, Page 40 of 132
Attachment 1, Volume 7, Rev. 0, Page 41 of 132 Improved Standard Technical Specifications (ISTS) Markup and Justification for Deviations (JFDs)
Attachment 1, Volume 7, Rev. 0, Page 41 of 132
Attachment 1, Volume 7, Rev. 0, Page 42 of 132 APSR Insertion Limits 3.2.2 CTS 3.2 POWER DISTRIBUTION LIMITS 3.2.2 AXIAL POWER SHAPING ROD (APSR) Insertion Limits 3.1.3.9 LCO 3.2.2 APSRs shall be positioned within the limits specified in the COLR.
APPLICABILITY: MODES 1 and 2.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME 3.1.3.9 A. APSRs not within limits. A.1 ---------- NOTE-------
Action a Only required when THERMAL POWER is
> 20% RTP.
Perform SR 3.2.5.1. Once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> AND A.2 Restore APSRs to within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> limits.
3.1.3.9 B. Required Action and 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 /> Action c associated Completion Time not met.
SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY 4.1.3.9 SR 3.2.2.1 Verify APSRs are within acceptable limits specified 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> in the COLR.
BVVOG STS 3.2.2-1 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 42 of 132
Attachment 1, Volume 7, Rev. 0, Page 43 of 132 JUSTIFICATION FOR DEVIATIONS ITS 3.2.2, AXIAL POWER SHAPING ROD (APSR) INSERTION LIMITS None Davis-Besse Page 1 of 1 Attachment 1, Volume 7, Rev. 0, Page 43 of 132
Attachment 1, Volume 7, Rev. 0, Page 44 of 132 Improved Standard Technical Specifications (ISTS) Bases Markup and Justification for Deviations (JFDs)
Attachment 1, Volume 7, Rev. 0, Page 44 of 132
Attachment 1, Volume 7, Rev. 0, Page 45 of 132 APSR Insertion Limits B 3.2.2 B13.2 POWER DISTRIBUTION LIMITS B 3.2.2 AXIAL POWER SHAPING ROD (APSR) Insertion Limits BASES BACKGROUND The insertion limits of the APSRs are initial condition assumptions in all safety analyses that are affected by core power distributions. The
.applicable criterion for these power distribution design requirements are
[10 CFR 50, Appen ix-Ar C 0, "Reactor Design" (Ref. 1), and UFSAR. Appendices(
10 CFR 50.46, "Acceptance Criteria for Emergency Core Cooling 3D.1.6 and 30.1.22 ]
Systems for Light Water Nuclear Power Plants" (Ref. 2).
are specified in the COLR Limits on APSR insertion[have beehn-qstablish~ed, and all APSR positions 0 are monitored and controlled during power operation to ensure that the power distribution defined by the design power peaking limits is maintained.
The power density at any point in the core must be limited to maintain specified acceptable fuel design limits, including limits that meet the criteria specified in Reference 2. Together, LCO 3.2.1, "Regulating Rod Insertion Limits," LCO 3.2.2, "AXIAL POWER SHAPING ROD (APSR)
Insertion Limits," LCO 3.2.3, "AXIAL POWER IMBALANCE Operating Limits," and LCO 3.2.4, "QUADRANT POWER TILT (QPT)," provide limits on control component operation and on monitored process variables to ensure that the core operates within the F0 , ) and F, limits in the COLR. Operation within the Fa limits given in the COLR prevents 0 linear heat rate !LR) power peaks that exceed the lo of coolant accident (LOCA) limits derived from the analysis of the Emergency Core Cooling Systems 0 (ECCS). Operation within the FA H limits given in the COLR prevents departure from nucleate boiling (DNB) during a loss of forced reactor coolant flow accident. The APSRs are not required for reactivity insertion rate on trip or SDM and, therefore, they do not trip upon a reactor trip.
This LCO is required to minimize fuel cladding failures that would breach
- the primary fission product barrier and release fission products to the reactor coolant in the event of a LOCA, loss of flow accident, ejected rod accident, or other postulated accident requiring termination by a Reactor Protection System trip function.
BWOG STS B 3.2.2-1 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 45 of 132
Attachment 1, Volume 7, Rev. 0, Page 46 of 132 APSR Insertion Limits B 3.2.2 BASES APPLICABLE The fuel cladding must not sustain damage as a result of normal SAFETY operation :(Condition 1) or anticipated Qperational occurrences ANALYSES (Condition 2). Acceptance criteria for the safety and regulating rod insertion, APSR position, AXIAL POWER IMBALANCE, and QPT LCOs preclude core power distributions that violate the following fuel design criteria:
- a. During a LOCA, the peak cladding temperature must not 0 exceed 2200°F (Ref. 2)_ _ 0 0
- b. During a loss of forced reactor coolant flow accident, there must be at least 95% probability at the 95% confidence level (the 95/95 DNB criterion) that the hot fuel rod in the core does not experience a DNB conditio ,
(Ref. 1)
- c. During an ejected rod accident, the fission energy input to the fuel 00 must not exceed 280 cal/gm (Ref. 3)m.and 0
- d. CONTROL RODS must be capable of shutting down the reactor with a minimum required SDM with the highest worth CONTROL ROD stuck fully withdrawn ( D 26,Ref. ).
0 Fuel cladding damage does not occur when the core is operated outside these LCOs during normal operation. However, fuel cladding damage could result should an accident occur simultaneously with violation of one or more of these LCOs. This potential for fuel cladding damage exists because changes in the power distribution can cause increased power peaking and corresponding increased localn rEatesl Operation at the APSR insertion limits may approach the maximum 0
allowable linear heat generation rate or peaking factor with the allowed QPT present.
The APSR insertion limits satisfy Criterion 2 of 10 CFR 50.36(c)(2)(ii).
BWOG STS B 3.2.2-2 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 46 of 132
Attachment 1, Volume 7, Rev. 0, Page 47 of 132 APSR Insertion Limits IB3.2.2 BASES LCO The limits on APSR physical insertion as defined in the COLR must be maintained because they serve the function of controlling the power distribution within an acceptable range.
The fuel cycle design assumes APSR withdrawal at the effective full power days (EFPD) burnup window specified in the COLR. Prior to this are maintained accordance withinthe0 window, the APSRs Icannot-ke maintaineo-. Ily withdrawn i--eaady state] (
rod operation the e.tioný After this window, the APSRs are not allowed to be reinserted recommendations for the remainder of the fuel cycle.
Error adjusted nax. um allowable spoints for APSR insertion are lmsprovided in the COLR. The,..*etintslare derived by adjustment of the measurement system independent limits to allow for THERMAL POWER level uncertainty and rod position errors.
Actual aarm setpoints imple.nented in the unit may L~e more restrictive than the 'naximum allowable . ,tpoint values to allow r additional (7 conservatism between the actaI alarm setpoints and the measurement system independent limits. ti APPLICABILITY The APSR physical insertion limits shall be maintained with the reactor in MODES 1 and 2. These limits maintain the power distribution within the range assumed linsOXkrion in the specified by tiaccident analyses./In s LCO maintain MOLfuel1,burnup the axial the limits on APSRJ/
design (
Icondnsasmdi t's reload safety evaluation a~talysis. In MODE 2,1
- applic"ii/s requied b*ause kef 2--0.99. /Applicability in MODES 3, 4, and 5 is not required, because the power distribution assumptions in the accident analyses would not be exceeded in these MODES.
ACTIONS For steady state power operation, a normal position for APSR insertion is
[rod operation specified in th stati n op&e ting proc..duresl The APSRs may be 0 ecommendations j positioned as necessary for transient AXIAL POWER IMBALANCE control until the fuel cycle design requires them to be fully withdrawn.
(Not all fuel cycles may incorporate APSR withdrawal.) APSRýp 0on limits are not imposed for gray APSRs, with two exceptions. If the fuel cycle design incorporates an APSR withdrawal (usually near end of cycle
{*r poitinedas *
(EOC)), the APSRs nay not be matained in the fully wit l'drawn position pnor tothetfucycrle urnup for the \.ýPSR withdrawal. If ttis occurs, h C) iloperation th od /APSRs must kbc restored to their norrb0al inserted position Conversely, Srecommendations jafter the fuel cycle burnup for the APSR withdrawal occurs, the APSRs I eo rtewihrwl.ccurs may not be reinserted for the remainder of the fuel cycle. These restrictions apply to ensure the axial burnup distribution that accumulates in the fuel will be consistent with the expected (as designed) distribution.
BWOG STS B 3.2.2-3 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 47 of 132
Attachment 1, Volume 7, Rev. 0, Page 48 of 132 APSR Insertion Limits B 3.2.2 BASES ACTIONS (continued)
A.1
'For verification that the core parameters FQMZ and:FHHare within their limits, SR 3.2.5.1 is performed using the Incore Detector System to obtain a three dimensional power distribution map. Successful verification that
'FQP) and F', are within their limits ensures that operation with the APSRs inserted or withdrawn in violation of the times specified in the COLR do not violate either the ECCS or DNB criteria (Ref. . The (5 required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is reasonable to allow the operator to obtain a power distribution map and to verify the power peaking factors. Repeating SR 3.2.5.1 every 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is reasonable to ensure that continued verification of the power peaking factors is -obtained as core conditions (primarily the regulating rod insertion and induced xenon redistribution) change.
Required Action A.1 is modified by a Note that requires the performance of SR 3.2.5.1 only when THERMAL POWER is greater than 20% RTP.
This establishes a Required Action that is consistent with the Applicability of LCO 3.2.5, "Power Peaking Factors."
A.2 Indefinite operation with the APSRs inserted or withdrawn in violation of the times specified in the COLR is not prudent. Even if power peaking monitoring per Required Action A.1 is continued, the abnormal APSR insertion or withdrawal may cause an adverse xenon redistribution, may cause the limits on AXIAL POWER IMBALANCE to be exceeded, or may affect the long term fuel depletion pattern. Therefore, power peaking monitoring is allowed for up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. This required Completion Time is reasonable based on the low probability of an event occurring simultaneously with the APSR limit out of specification. In addition, it precludes long term depletion with the APSRs in positions that have not been analyzed, thereby limiting the potential for an adverse xenon redistribution. This time limit also ensures that the intended burnup distribution is maintained, and allows the operator sufficient time to reposition the.APSRs to correct their positions.
Because the APSRs are not operated by the automatic control system, manual action by the operator is required to restore the APSRs to the positions specified in the COLR.
BWOG STS B 3.2.2-4 Rev. 3.0, 03/31104 Attachment 1, Volume 7, Rev. 0, Page 48 of 132
Attachment 1, Volume 7, Rev. 0, Page 49 of 132 APSR Insertion Limits B 3.2.2 BASES ACTIONS (continued)
B.1 any Required Action and associated Completion Time is not met lfjthe TPSRs cannot be re'.tored to their intended 'p. sitions within the require\d Completion Time ol(24 hour/ the reactor must be placed in MODE 3, in which this LCO does not apply. This action ensures that the fuel does not continue to be depleted in an unintended burnup distribution. The required 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 regarding the time required to reach MODE 3 from RTP in an orderly manner and without challenging plant systems.
SURVEILLANCE SR 3.2.2.1 REQUIREMENTS Fuel cycle designs that allow APSR withdrawal near EOC do not permit reinsertion of APSRs after the time of withdrawal. VV~en the plant com~uter is OPERABLE, the opbrator will receive a co.. puter alarm if the IAPSR~s insert after that~time in cor~elife when the APSR`\ ithdrawal/-
0 locr.JVerification that the APSRs are within their insertion limits at a 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Frequency is sufficient to ensure that the APSR insertion limits are preserved land the computer aarm remains L PERABLE1 The 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Frequency required for performing this verification is sufficient because APSRs are positioned by manual control and are normally moved infrequently. The proba flity of a deviation odcurringý simultan ously with an ino erable\com uter alarm is Ikwin this relatively0 Ishort time~frame.*AAlso, *e Frequency takes into account other information available in the control room for monitoring the axial power distribution in the reactor core.
REFERENCES 1 1C0. 50, Appen A, GDC 10 dGDC26.
- 2. 10 CFR 50.46.
El. FSAR, Section 15.4.3
.I UFSAR. Appendix 301 23 B GBFT3AR,ptRr.300/1 .2ýh FBAW- 1-0179P-A, "Safety Criteria and Methodology for Acceptance (ycle Reload Analyses" (revision specified in Specification 5.6.3)
BVVOG STS B 3.2.2-5 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 49 of 132
Attachment 1, Volume 7, Rev. 0, Page 50 of 132 JUSTIFICATION FOR DEVIATIONS ITS 3.2.2 BASES, AXIAL POWER SHAPING ROD (APSR) INSERTION LIMITS
- 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. These punctuation corrections have been made consistent with the Writer's Guide for the Improved Standard Technical Specifications, TSTF-GG-05-01, Section 5.1.3.
- 3. Changes are made to reflect the Specification.
- 4. The brackets have been removed and the proper plant specific information/value has been provided.
- 5. Davis-Besse was designed and under construction prior to the promulgation of 10 CFR 50, Appendix A. The design of Davis-Besse meets the intent of 10 CFR 50, Appendix A published in the Federal Register on February 20, 1971, and as amended in Federal Register on July 7, 1971. Bases references to the 10 CFR 50, Appendix A criteria have been replaced with references to the appropriate section of the UFSAR.
- 6. The ISTS LCO 3.2.2 Bases includes a discussion of "Actual Alarm Setpoints" for APSR insertion limits. This discussion is not included in the ITS LCO 3.2.2 Bases.
The "Actual Alarm Setpoints" are not needed to satisfy the requirements of the LCO and therefore a discussion of the "Actual Alarm Setpoints" is not needed in the LCO Bases.
- 7. Changes are made to be consistent with other places in the Bases (i.e., LCO 3.2.5 Bases Background).
- 8. Changes are made to reflect changes made to the Specification.
Davis-Besse Page 1 of 1 Attachment 1, Volume 7, Rev. 0, Page 50 of 132
Attachment 1, Volume 7, Rev. 0, Page 51 of 132 Specific No Significant Hazards Considerations (NSHCs)
Attachment 1, Volume 7, Rev. 0, Page 51 of 132
Attachment 1, Volume 7, Rev. 0, Page 52 of 132 DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATIONS ITS 3.2.2, AXIAL POWER SHAPING ROD (APSR) INSERTION LIMITS There are no specific NSHC discussions for this Specification.
Davis-Besse Page 1 of 1 Attachment 1, Volume 7, Rev. 0, Page 52 of 132
Attachment 1, Volume 7, Rev. 0, Page 53 of 132 ATTACHMENT 3 ITS 3.2.3, AXIAL POWER IMBALANCE OPERATING LIMITS Attachment 1, Volume 7, Rev. 0, Page 53 of 132
, Volume 7, Rev. 0, Page 54 of 132 Current Technical Specification (CTS) Markup and Discussion of Changes (DOCs) , Volume 7, Rev. 0, Page 54 of 132
Attachment 1, Volume 7, Rev. 0, Page 55 of 132 ITS 3.2.3 ITS 314.2 POWER DISTRIBUTION LIMITS AXIAL POWER IMBALANCE LIMITING CONDITION FOR OPERATION 3.2.1 AXIAL POWER IMBALANCE shall be maintained within the acceptable AXIAL LCO 3.2.3 POWER IMBALANCE operating limits provided in the CORE OPERATING LIMITS REPORT. I APPLICABILITY: MODE 1 above 40' of RATED THERMAL POWER. A02 ACTION:
With AXIAL POWER IMBALANCE exceeding the limits specified abov eithe: pRequiredActionA1 /
ACTION A
- a. Restore the AXIAL POWER IMBALANCE to wi h the limits provided in the CORE OPERATING LIMITS REPORT within 15 m* utes, or 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> ACTION B b. Within reduce power until imbalance limits provided in the CORE OPERATING LIMITS REPORT are met or to 40% of RATED THERMAL POWER or less.
SURVEILLANCE REQUIREMENTS 4.2.1 The AXIAL POWER IMBALANCE shall be determined to be within the limits provided in the CORE OPERATING LIMITS REPORT at least once ever 1 hours1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> SR 3.2.3.1 when above 4O0 of RATED THERMAL POWER except/when the AXIAL POWE; IMBALANCE alarm is inoperab1 , then calculate the AXI!L POWER IMBALANCE at least once / L03 per hour._/
I*See pecial t Exceptio 3.10.1. A02 DAVIS-BESSE, UNIT 1 3/4 2-1 Amendment No. ,
(Next page is 3/4 2-5) 80,;Z;, 144 Page 1 of 1 Attachment 1, Volume 7, Rev. 0, Page 55 of 132
Attachment 1, Volume 7, Rev. 0, Page 56 of 132 DISCUSSION OF CHANGES ITS 3.2.3, AXIAL POWER IMBALANCE OPERATING LIMITS ADMINISTRATIVE CHANGES A01 In the conversion of the Davis-Besse 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-1430, Rev. 3.1, "Standard Technical Specifications-Babcock and Wilcox Plants" (ISTS).
These changes are designated as administrative changes and are acceptable because they do not result in technical changes to the CTS.
A02 The Applicability of CTS 3.2.1 is MODE 1 above 40% RATED THERMAL POWER with footnote
- stating "See Special Test Exception 3.10.1." ITS 3.2.3 Applicability is MODE 1 above 40% RATED THERMAL POWER and does not contain the footnote or a reference to the Special Test Exception. This changes the CTS by deleting explicit reference to the Special Test Exception.
The purpose of the footnote reference is to alert the user that a Special Test Exception exists that may modify the Applicability of the Specification. It is an ITS convention to not include these types of footnotes or cross-references. This change is designated as administrative as it incorporates an ITS convention with no technical change to the CTS.
MORE RESTRICTIVE CHANGES None RELOCATED SPECIFICATIONS None REMOVED DETAIL CHANGES None LESS RESTRICTIVE CHANGES L01 (Category 3 - Relaxation of Completion Time) CTS 3.2.1 Action a requires the restoration of AXIAL POWER IMBALANCE to be within limits within 15 minutes.
ITS 3.2.3 ACTION A requires the performance of ITS SR 3.2.5.1 (Verify FQ and F, Hare within limits by using the Incore Detector System to obtain a power distribution map) once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and the restoration of the AXIAL POWER IMBALANCE to within limits within 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 extending the Completion Time from "15 minutes" to "24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />" and provides a requirement to verify FQ and F. H are within their limits once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />.
Davis-Besse Page 1 of 4 Attachment 1, Volume 7, Rev. 0, Page 56 of 132
Attachment 1, Volume 7, Rev. 0, Page 57 of 132 DISCUSSION OF CHANGES ITS 3.2.3, AXIAL POWER IMBALANCE OPERATING LIMITS The purpose of CTS 3.2.1 Action a is to restore AXIAL POWER IMBALANCE to ensure that the axial burnup distribution that accumulates in the fuel will be consistent with the expected (as designed) distribution. This change is acceptable because the Completion Time is consistent with safe operation under the specified Condition, considering a reasonable time for restoration and the low probability of a DBA occurring during the allowed Completion Time. This changes the CTS by extending the Completion Time to restore AXIAL POWER IMBALANCE operating limits from "15 minutes" to "24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />" and provides a requirement to verify Fa and F. H are within their limits once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. The AXIAL POWER IMBALANCE operating limits that maintain the validity of the assumptions regarding the power distributions in the accident analyses of the LOCA and the loss of flow accident are provided in the COLR. Operation within the AXIAL POWER IMBALANCE limits given in the COLR is the acceptable region of operation. Operation in violation of the AXIAL POWER IMBALANCE limits given in the COLR is the restricted region of operation. Operation with AXIAL POWER IMBALANCE in the restricted region shown on the AXIAL POWER IMBALANCE figures in the COLR potentially violates the LOCA LHR limits (FQ limits) or the loss of flow accident DNB peaking limits F. H limits) or both. For verification that FQ and F.H are within their specified limits, SR 3.2.5.1 is performed using the Incore Detector System to obtain a three dimensional power distribution map. Verification that FQ and F. Hare within their specified limits ensures that operation with the AXIAL POWER IMBALANCE in the restricted region does not violate the ECCS or 95/95 DNB criteria. The required 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 reasonable time for the operator to obtain a power distribution map and to determine and verify that the power peaking factors are within their specified limits. The 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> Frequency provides reasonable time to ensure that continued verification of the power peaking factors is obtained as core conditions (primarily regulating rod insertion and induced xenon redistribution) change, because little rod motion occurs in 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> due to fuel burnup, the potential for xenon redistribution is limited, and the probability of an event occurring in this short time frame is low. Indefinite operation with the AXIAL POWER IMBALANCE in the restricted region is not prudent. Even if power peaking monitoring per Required Action A.1 is continued, excessive AXIAL POWER IMBALANCE over an extended period of time may cause a potentially adverse xenon redistribution to occur. Therefore, power peaking monitoring is only allowed for a maximum of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. This required Completion Time is reasonable based on the low probability of a limiting event occurring simultaneously with the AXIAL POWER IMBALANCE outside the limits of this LCO. In addition, this limited Completion Time precludes long term depletion of the reactor fuel with excessive AXIAL POWER IMBALANCE and gives the operator sufficient time to reposition the APSRs or regulating rods to reduce the AXIAL POWER IMBALANCE because adverse effects of xenon redistribution and fuel depletion are limited. This change is designated as less restrictive because additional time is allowed to restore AXIAL POWER IMBALANCE to within the LCO limits than was allowed in the CTS.
L02 (Category 3 - Relaxation of Completion Time) In the event the AXIAL POWER IMBALANCE exceeds the limits, CTS 3.2.1 Action b requires power to be reduced until the imbalance limits are met or to be < 40% RTP within one hour, as one of two alternative actions. ITS 3.2.3, Required Action B.1 requires Davis-Besse Page 2 of 4 Attachment 1, Volume 7, Rev. 0, Page 57 of 132
Attachment 1, Volume 7, Rev. 0, Page 58 of 132 DISCUSSION OF CHANGES ITS 3.2.3, AXIAL POWER IMBALANCE OPERATING LIMITS THERMAL POWER to be reduced to _ 40% RTP within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> if the Required Actions and Completion Times of Condition A (AXIAL POWER IMBALANCE not within limits) are not met. This change revises the CTS Action by extending the total time allowed to reduce THERMAL POWER to _< 40% RTP from 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> to 26 hours3.009259e-4 days <br />0.00722 hours <br />4.298942e-5 weeks <br />9.893e-6 months <br /> (the Required Actions of ITS 3.2.3 Condition A provides a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Completion Times prior to Condition B being entered). The justification for the Completion Time of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is discussed in Discussion of Change L01.
The purpose of the CTS 3.2.1 Action b is to ensure that the AXIAL POWER IMBALANCE is restored so that the assumptions regarding the power distributions in the accident analyses are valid or to be in a condition where the AXIAL POWER IMBALANCE limits are not applicable. 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. This includes the capacity and capability of remaining systems or features, a reasonable time for repairs or replacement, and the low probability of a DBA occurring during the allowed Completion Time. This change revises the CTS Action by extending the total time allowed to reduce THERMAL POWER to _<40% RTP from 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> to 26 hours3.009259e-4 days <br />0.00722 hours <br />4.298942e-5 weeks <br />9.893e-6 months <br /> (the Required Actions of ITS 3.2.3 Condition A provides a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Completion Times prior to Condition B being entered). The acceptability of the 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Completion Time is justified in DOC L01. This change is concerned with the relaxation of the Completion Time to reach 40% RTP from "one hour" to "2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />." The revised Completion Time allows reactor power to be reduced in a controlled manner without challenging operators or plant systems. This change is designated as less restrictive because additional time is allowed to reduce power than was allowed in the CTS.
L03 (Category 7- Relaxation of Surveillance Frequency - Non-24 Month Type Change) CTS 4.2.1 requires the AXIAL POWER IMBALANCE to be determined to be within operating limits at least once every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> except during time intervals when the AXIAL POWER IMBALANCE alarm is inoperable. With this alarm inoperable, CTS 4.2.1 requires the verification that AXIAL POWER IMBALANCE is within limits at least once per hour. ITS SR 3.2.3.1 requires verification that AXIAL POWER IMBALANCE is within 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 verify that AXIAL POWER IMBALANCE is within the limits at least once per hour when the AXIAL POWER IMBALANCE alarm is inoperable.
The purpose of CTS 4.2.1 is to periodically verify that the AXIAL POWER IMBALANCE is within the limits. This change is acceptable because increasing the Frequency of AXIAL POWER IMBALANCE operating limit verification when the AXIAL POWER IMBALANCE alarm is inoperable is unnecessary. An inoperability of the alarm does not increase the probability that the AXIAL POWER IMBALANCE limits are not met. 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 3.2.3.1) continues to ensure the AXIAL FLUX IMBALANCE limits are met.
Furthermore, the AXIAL POWER IMBALANCE limit alarm is for indication only.
Its use is not credited in any safety analyses. Thus, any response determined necessary by plant personnel due to an inoperable alarm is more appropriately controlled by plant procedures, not Technical Specifications. This change is Davis-Besse Page 3 of 4 Attachment 1, Volume 7, Rev. 0, Page 58 of 132
Attachment 1, Volume 7, Rev. 0, Page 59 of 132 DISCUSSION OF CHANGES ITS 3.2.3, AXIAL POWER IMBALANCE OPERATING LIMITS designated as less restrictive because Surveillances will be performed less frequently under the ITS than under the CTS.
Davis-Besse Page 4 of 4 Attachment 1, Volume 7, Rev. 0, Page 59 of 132
Attachment 1, Volume 7, Rev. 0, Page 60 of 132 Improved Standard Technical Specifications (ISTS) Markup and Justification for Deviations (JFDs)
Attachment 1, Volume 7, Rev. 0, Page 60 of 132
Attachment 1, Volume 7, Rev. 0, Page 61 of 132 AXIAL POWER IMBALANCE Operating Limits 3.2.3 CTS 3.2 POWER DISTRIBUTION LIMITS 3.2.3 AXIAL POWER IMBALANCE Operating Limits 3.2.1 LCO 3.2.3 AXIAL POWER IMBALANCE shall be ;maintained within the limits specified 'in the COLR, APPLICABILITY: MODE 1 with THERMAL POWER > 40% RTP.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME 3.2.1 Action a A. AXIAL POWER A.1 Perform SR 3.2.5.1. Once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> IMBALANCE not within limits. AND A.2 Reduce AXIAL POWER 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> IMBALANCE within limits.
3.2.1 B. Required Action and B.1 Reduce THERMAL 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> Action b associated Completion POWER to _ 40% RTP.
Time not met.
SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY 4.2.1 SR 3.2.3.1 Verify AXIAL POWER IMBALANCE is within limits 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> as specified in the COLR.
BWAOG STS 3.2.3-1 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 61 of 132
Attachment 1, Volume 7, Rev. 0, Page 62 of 132 JUSTIFICATION FOR DEVIATIONS ITS 3.2.3, AXIAL POWER IMBALANCE OPERATING LIMITS None.
Davis-Besse Page 1 of 1 Attachment 1, Volume 7, Rev. 0, Page 62 of 132
Attachment 1, Volume 7, Rev. 0, Page 63 of 132 Improved Standard Technical Specifications (ISTS) Bases Markup and Justification for Deviations (JFDs)
Attachment 1, Volume 7, Rev. 0, Page 63 of 132
Attachment 1, Volume 7, Rev. 0, Page 64 of 132 AXIAL POWER IMBALANCE Operating Limits B 3.2.3 B 3.2 POWER DISTRIBUTION LIMITS B 3.2.3 AXIAL POWER IMBALANCE Operating Limits BASES BACKGROUND This LCO is required to limit the core power distribution based on accident initial condition criteria.
The power density at any point in the core ,must be limited to maintain specified acceptable fuel design limits, including limits that satisfy the criteria specified in 10 CFR 50.46 (Ref. 1). This LCO provides limits on AXIAL POWER IMBALANCE to ensure that the core operates within the Fa ,)] and FH limits given in the COLR. Operation within the F Q4limits given in the COLR prevents power peaks that exceed the loss of coolant linear heat rate (LHR accident (LOCA)tlimits derived from the analysis of the Emergency Core Cooling Systems (ECCS). Operation within the FAH limits given in the COLR prevents departure from nucleate boiling (DNB) during a loss of forced reactor coolant flow accident.
This LCO is required to limit fuel cladding failures that breach the primary fission product barrier and release fission products into the reactor coolant in the event of a LOCA, loss of forced reactor coolant flow accident, or other postulated accident requiring termination by a Reactor Protection System trip function. This LCO limits the amount of damage to the fuel cladding during an accident by maintaining the validity of the assumptions in the safety analyses related to the initial power distribution and reactivity.
Fuel cladding failure during a postulated LOCA is limited by restricting the maximum linear heat rate (LHR) so that the peak cladding temperature does not exceed 2200°F (Ref. 2). Peak cladding temperatures > 2200°F cause severe cladding failure by oxidation due to a Zircaloy water reaction. Other criteria must also be met (e.g., maximum cladding oxidation, maximum hydrogen generation, coolable geometry, and long term cooling). However, peak cladding temperature is usually most limiting.
Proximity to the DNB condition is expressed by the departure from nucleate boiling ratio (DNBR), defined as the ratio of the cladding surface heat flux required to cause DNB to the actual cladding surface heat flux.
The minimum DNBR value during both normal operation and anticipated transients is limited to the DNBR correlation limit for the particular fuel design in use and is accepted as an appropriate margin to DNB. The DN B correlation limit ensures that there is at least 95% probability at the 95% confidence level (the 95/95 DNB criterion) that the hot fuel rod in the core does not experience DNB.
BWOG STS B 3.2.3-1 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 64 of 132
Attachment 1, Volume 7, Rev. 0, Page 65 of 132 AXIAL POWER IMBALANCE Operating Limits B 3.2.3 BASES BACKGROUND (continued)
The measurement system independent limits on AXIAL POWER
- IMBALANCE are determined directly by the reload safety evaluation analysis without adjustment.for measurement system error and uncertainty. Operation beyond these limits could invalidate the
.assumptions Used in the accident analyses regarding the core power distribution.
APPLICABLE The fuel cladding must not sustain damage as a result of normal SAFETY ,operation (Condition 1) and anticipated operational occurrences ANALYSES (Condition 2). The LCOs based on power distribution, LCO 3.2.1, "Regulating Rod Insertion Limits," LCO 3.2.2, "AXIAL POWER SHAPING ROD (APSR) Insertion Limits," LCO 3.2.3, "AXIAL POWER IMBALANCE Operating Limits," and LCO 3.2.4, "QUADRANT POWER TILT (QPT),"
preclude core power distributions that would violate the following fuel design criteria:
- a. During a aLOCA, peak cladding temperature must not 0 D
exceed 2200°F (Ref. 1)1*
0
- b. During a loss of forced reactor coolant flow accident, there must be at least a 95% probability at the 95% confidence level (the 95/95 DNB criterion) that the hot fuel rod in the core does not experience a DNB condition
- ( INSERT 1 0 The regulating rod positions, the APSR positions, the AXIAL POWER IMBALANCE, and the QPT are process variables that characterize and control the three dimensional power distribution of the reactor core.
Fuel cladding damage does not occur when the core is operated outside this LCO during normal operation. However, fuel cladding damage could result should an accident occur with simultaneous violation of one or more of the LCOs governing the four process variables cited above. This potential for fuel cladding damage exists because changes in the power distribution can cause increased power peaking and corresponding increased local LHRs.
BWOG STS B 3.2.3-2 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 65 of 132
Attachment 1, Volume 7, Rev. 0, Page 66 of 132 B 3.2.3 O* INSERT I
- c. During an ejected rod accident, the fission energy input to the fuel must not exceed 280 cal/gm (Ref. 3); and
- d. The CONTROL RODS must be capable of shutting down the reactor with a minimum required SDM with the highest worth CONTROL ROD stuck fully withdrawn (Ref. 4).
Insert Page B 3.2.3-2 Attachment 1, Volume 7, Rev. 0, Page 66 of 132
Attachment 1, Volume 7, Rev. 0, Page 67 of 132 AXIAL POWER IMBALANCE Operating Limits B 3.2.3 BASES APPLICABLE SAFETY ANALYSES (continued)
The regulating rodainsertion, the APSR positions, the AXIAL POWER IMBALANCE, .and the QPT are monitored and controlled during power operation to ensure that the power distribution is within the bounds set by the safety analyses. The axial power distribution is maintained primarily by the AXIAL POWER IMBALANCE and the APSR omits; and Q the radial power distribution is maintained primarily by the QPT limits. "
The regulating rod insertion limits affect both the radial and axial power distributions.
The dependence of the core power distribution on burnup, regulating rod insertion, APSR position, and spatial xenon distribution is taken into account when the reload safety evaluation analysis is performed.
Operation at the AXIAL POWER IMBALANCE limit must be interpreted as operating the core at the maximum allowable FcRl or FA H peaking Q factors assumed as initial conditions for the accident analyses with the allowed QPT present.
AXIAL POWER IMBALANCE satisfies Criterion 2 of 10 CFR 50.36(c)(2)(ii).
LCO The power distribution LCO limits have been established based on correlations between power peaking and easily measured process variables: regulating rod position, APSR position, AXIAL POWER IMBALANCE, and QPT. The AXIAL POWER IMBALANCE envelopel (9 contained in the COLR represents the setintor which the core power distribution would either exceed the LOCA LHR limits or cause a reduction in the DN BR below the Safety Limit during the loss of flow accident with the allowable QPT present and with the APSR positions consistent with the limitations on APSR withdrawal determined by the fuel cycle design and specified by LCO 3.2.2.
Operaton beyond the power distribution based LCC. limits for the corresp. nding ALLOWABLE THERMAL POWER ar\: simultaneous occurren e of either the LOC. or loss of forced react r coolant flow accident I as an acceptably lo probability. Therefore if the LCO limits are violate'l, a short time is allkwed for corrective actio, before a 0
significant power reduction is re uired.
BWOG STS B 3.2.3-3 Rev. 3.0, 03/31104 Attachment 1, Volume 7, Rev. 0, Page 67 of 132
Attachment 1, Volume 7, Rev. 0, Page 68 of 132 AXIAL POWER IMBALANCE Operating Limits B 3.2.3 BASES LCO (continued) liit The AXIAL POWER IMBALANCE jmajpunum ai~wable se points (measurement system dependent limits) applicable for the IjUI Incore Detector Systeml the i.inimum Ir pre Detecto,-System,iand the Excore Detector System are provided in the COLR.
Actual ailarm setpoints impl Tented in the unit may 'ie more restrictive than the 'aximum allowable, etpoint values to provide additional conservati rm between the actLal alarm setpoints and ,.e measurement 0 system ind ,pendent limit.
APPLICABILITY In MODE 1, the limits on AXIAL POWER IMBALANCE must be maintained when THERMAL POWER is > 40% RTP to prevent the core power distribution from exceeding the LOCA and loss of flow assumptions used in the accident analyses. Applicability of these limits at < 40% RTP in MODE 1 is not required. This operation is acceptable because the combination of AXIAL POWER IMBALANCE with the maximum allowable THERMAL POWER level will not result in LHRs sufficiently large to violate the fuel design limits. In MODES 2, 3, 4, 5, and 6, this LCO is not applicable because the reactor is not generating sufficient THERMAL POWER to produce fuel damage.
In MODE 1, it may be necessary to suspend the AXIAL POWER IMBALANCE limits during PHYSICS TESTS per LCO 3.1.8, "PHYSICS TESTS Exceptions - MODE 1." Suspension of these limits is permissible because the reactor protection criteria are maintained by the remaining LCOs governing the three dimensional power distribution and by the Surveillances required by LCO 3.1.8.
ACTIONS A.1 The AXIAL POWER IMBALANCE operating limits that maintain the validity of the assumptions regarding the power distributions in the accident analyses of the LOCA and the loss of flow accident are provided in the COLR. Operation within the AXIAL POWER IMBALANCE limits given in the COLR is the acceptable region of operation. Operation in violation of the AXIAL POWER IMBALANCE limits given in the COLR is the restricted region of operation.
Operation with AXIAL POWER IMBALANCE in the restricted region shown on the AXIAL POWER IMBALANCE figures in the COLR potentially violates the LOCA LHR limits (FQo 2-) limits) or the loss of flow 0 accident DNB peaking limits FAH limits) or both. For verification that BWOG STS B 3.2.3-4 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 68 of 132
Attachment 1, Volume 7, Rev. 0, Page 69 of 132 AXIAL POWER IMBALANCE Operating Limits B 3.2.3 BASES ACTIONS (continued)
FQ, and F'AH are within their specified limits, SR 3.2.5.1 is performed Q using the Incore Detector System to obtain a three dimensional !power distribution map. Verification that .Fc]and FA Hare within their specified Q limits ensures that operation with the.AXIAL POWER IMBALANCE in the restricted region does not violate the ECCS or 95/95 DNB criteria. The required 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 reasonable time for the operator to obtain a power distribution map and to determine and verify that the power peaking factors are within their specified limits. The 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> Frequency provides reasonable time to ensure that continued verification of the power peaking factors is obtained as core conditions (primarily regulating rod insertion and induced xenon redistribution) change, because little rod motion occurs .in 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> due to fuel burnup, the potential for xenon redistribution is limited, and the probability of an event occurring in this short time frame is low.
A.2 Indefinite operation with the AXIAL POWER IMBALANCE in the restricted region is not prudent. Even if power peaking monitoring per Required Action A.1 is continued, excessive AXIAL POWER IMBALANCE over an extended period of time may cause a potentially adverse xenon redistribution to occur. Therefore, power peaking monitoring is only allowed for a maximum of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. This required Completion Time is reasonable based on the low probability of a limiting event occurring simultaneously with the AXIAL POWER IMBALANCE outside the limits of this LCO. In addition, this limited Completion Time precludes long term depletion of the reactor fuel with excessive AXIAL POWER IMBALANCE and gives the operator sufficient time to reposition the APSRs or regulating rods to reduce the AXIAL POWER IMBALANCE because adverse effects of xenon redistribution and fuel depletion are limited.
B.1 any If t e Required Actiong and Rý7-ijassociated Completion Time---
met, the AXIAL POWER IMBALANCE may exceed its specified limits and the reactor may be operating with a global axial power distribution mismatch. Continued operation in this configuration may induce an axial xenon oscillation and may result in an increased linear heat generation rate when the xenon redistributes. Reducing BWAOG STS B 3.2.3-5 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 69 of 132
Attachment 1, Volume 7, Rev. 0, Page 70 of 132 AXIAL POWER IMBALANCE Operating Limits B 3.2.3 BASES ACTIONS (continued)
THERMAL POWER to - 40% RTP reduces the maximum LHR:to .a value that does 1not exceed the FQM and AFH initial condition limits assumed in the accident analyses. The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is reasonable based on limiting a potentially adverse xenon redistribution, the low probability of an accident occurring in this relatively Short time period, and the number of steps required to complete this Action.
SURVEILLANCE The AXIAL POWER IMBALANCE can be monitored by both the Incore REQUIREMENTS and Excore Detector Systems. TheAXIAL POWER IMBALANCE maximum allowableetp ints are derived from their corresponding measurement system independent limits by adjusting for both the system observability errors and instrumentation errors. Although they may be based on the same measurement system independent limits, the setpoints for the different systems are not identical because of differences in the errors applicable for each of these systems. The uncertainty maxbimum analysis that defines the required error adjustment to convert the allowable limits measurement system independent limits -oalarm toints assumes that incore 75% o t e detectors in each quadrant are OPERABLE. Detectors /
located on the core major axes re assumed to contribute* one half of their output to e, ch quadrant; detectcgs in the center assembly re assumed to contribute cne quarter of their outpout to each quadrant. For IAL POWER IM ALANCE measurements using the Incore Dete or System, the Minimurr Incore Detector Syste, consists of OPERABLE etectors configured a- follows:/
- a. Nin~ detectors shall be arranged such that there\are three detectors 0 in e- ch of three strings ai d there are three detect rs lying in the same axial plane, with one plane at the core midplzae and one plane in eac .\axial core half,
- b. I heaxlal planes in eaci.icore halt Shall be sym rtcal a out the core idplane, and \
- c. Th"detector strin"§shall not have ra al symmetry.
Figure _ 3.2.3-1 (Minimum lrcore Detector System fo\[ AXIAL POWER IMBALA CE Measurement) cepicts an example of thi* configuration.
This arrai gement is chosen to reduce the uncertainty ih the measuren ent of the AXIAL POWER IMBALANCE by th. Minimum Incore Detector S. stem. For example, the requirement for placing one detector of each of t \e three strings at th. core midplane puts thref detectors in BWAOG STS B 3.2.3-6 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 70 of 132
Attachment 1, Volume 7, Rev. 0, Page 71 of 132 AXIAL POWER IMBALANCE Operating Limits B 3.2.3 BASES SURVEILLANCE REQUIREMENTS (continued) the central region of the core where the neutron flux tends to be higher. It also hell s prevent measuring an AXIAL POWER IMB-\LANCE .that is excessivý'ly large When the rei ctor is operating at low IH ERMAL POWER vels. The third requirement for placement of detectors (Le..,
0 radial asyrt metry) reduces unc\rtainty by measuring the\ eutron flux at core locati-ns that are not radialVy symmetric.
SR 3.2.3.1 Verification of the AXIAL POWER IMBALANCE indication every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> ensures that the AXIAL POWER IMBALANCE limits are not violated and takes into account other information n arms available to the operator in the control room. This Surveillance Frequency is acceptable because 0
the mechanisms that can cause AXIAL POWER IMBALANCE, such as xenon redistribution orCONTROL ROD drive mechanism malfunctions that cause slow AXIAL POWER IMBALANCE increases, can be discovered by the operator before the specified limits are violated.
REFERENCES 1. 10CFR50.46.
- 2. -FSAR,jChaptr[15] ý Son6.3 Inm5 J
- 3. UFSAR. Section 15.4.3.
- 4. UFSAR, Appendix 3D.1.23.
0 BWOG STS B 3.2.3-7 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 71 of 132
0 , Volume 7, Rev. 0, Page 72 of 132
Attachment 1, Volume 7, Rev. 0, Page 73 of 132 JUSTIFICATION FOR DEVIATIONS ITS 3.2.3 BASES, AXIAL POWER IMBALANCE OPERATING LIMITS
- 1. These punctuation corrections have been made consistent with the Writer's Guide for the Improved Standard Technical Specifications, TSTF-GG-05-01, Section 5.1.3.
- 2. Changes are made to reflect other places in the Bases.
- 3. Changes are made to reflect changes made to the Specification.
- 4. 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.
- 5. The brackets have been removed and the proper plant specific information/value has been provided.
- 6. Changes are made to be consistent with other places in the Bases (i.e., LCO 3.2.5 Bases Background).
- 7. The ISTS LCO 3.2.3 Bases includes a discussion of "Actual Alarm Setpoints" for AXIAL POWER IMBALANCE operating limits. This discussion is not included in the ITS LCO 3.2.3 Bases. The "Actual Alarm Setpoints" are not needed to satisfy the requirements of the LCO and therefore a discussion of the "Actual Alarm Setpoints" is not needed in the LCO Bases.
Davis-Besse Page 1 of 1 Attachment 1, Volume 7, Rev. 0, Page 73 of 132
Attachment 1, Volume 7, Rev. 0, Page 74 of 132 Specific No Significant Hazards Considerations (NSHCs)
Attachment 1, Volume 7, Rev. 0, Page 74 of 132
Attachment 1, Volume 7, Rev. 0, Page 75 of 132 DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATIONS ITS 3.2.3, AXIAL POWER IMBALANCE OPERATING LIMITS There are no specific NSHC discussions for this Specification.
Davis-Besse Page 1 of 1 Attachment 1, Volume 7, Rev. 0, Page 75 of 132
, Volume 7, Rev. 0, Page 76 of 132 ATTACHMENT 4 ITS 3.2.4, QUADRANT POWER TILT (QPT) , Volume 7, Rev. 0, Page 76 of 132
, Volume 7, Rev. 0, Page 77 of 132 Current Technical Specification (CTS) Markup and Discussion of Changes (DOCs) , Volume 7, Rev. 0, Page 77 of 132
Attachment 1, Volume 7, Rev. 0, Page 78 of 132 ITS 0 ITS 3.2.4 POWER DISTRIBUTION LIMITS QUADRANT POWER TILT LIMITING CONDITION FOR OPERATION 3.2.4 THE QUADRANT POWER TILT shall not exceed the Steady State Limit for LCO 3.2.4 QUADRANT POWER TILT provided in the CORE OPERATING LIMITS REPORT.
APPLICABILITY: MODE I above 5 of RATED THERMAL POWER.P_
ACTION:
- a. With the QUADRANT POWER TILT determined to exceed the Steady State Limit but less than or equa.l to the Transient Limit provided inthe CORE OPERATING LIMITS REPORT:- Add proposed 1 . V i t h i n 2 h o u rs - , e ur d c o . .
Stea dY State Limit, r POE 1\owtiis b) Reduce THERMAL POWER so as not to exceed THERMAL POWER, ACTION A including power level cutoff, allowable for the reactor coolant pump conbination less at least 2% for each 1% of QUADRANT POWER TILT in excess of the Steady State Limit L02 and within[fours. reduce the High Flux Trip Setpoint and the Flux-A Flux-Flow Trip Setpolnt at least 2% for each 1% of QUADRANT POWER TILT in excess of the Steady State Limit.
- 2. Verify that the QUADRANT POWER TILT is within its Steady State Limit within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after exceeding the Steady State Limit or reduce THERMAL POWER to less than 60% of THERMAL POWER allowable for the reactor coolant pump combination within the ACTION C next 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and reduce the High Flux Trip Setpoint to < 65.5%
of THERMAL POWER allowable fort the reactor coolant pump-combination within the nexL 4hours.
SR 3.2.4.1 3. Identify and correct the cause of the out of limit condition prior to increasing THERMAL POWER; subsequent POWER OPERATION above 60% of THEIRAL POWER allowable for the reactor coolant
- y. h;l Ii 0-Ii .. -l A VpriW~~~u tj-t.1U th. ni~D roIWI F-F ý.. 9 . .. j r . r TILT is verified within its Steady State Limit at least once per hour for 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> or until verified acceptable at 95% or greater RATED THERMAL POWER.
1;Add proposed ACTIOD M0I1 L*See -*ecial Tes* Exception .. O.10.1.
A02 DAVIS-BESSE, UNIT ? 3/4 2-9 Amendment No. U3I, 144 Page 1 of 3 Attachment 1, Volume 7, Rev. 0, Page 78 of 132
Attachment 1, Volume 7, Rev. 0, Page 79 of 132 ITS 3.2.4 ITS POWER DISTRIBUTION LIMITS LIMITING CONDITION FOR OPERATION (Continued)
ACTION: (Continued)
- b. With the QUADRANT POWER TILT determined to exceed the Transient Limit but less than the Maximum Limit provided in the CORE OPERATING LIMITS REPORT, due to misalignment of either a safety, regulating or axial ACTION B power shaping rod:
- 1. Reduce THERMAL POWER at least 2% for each 1% of indicated QUADRANI POWER TILT in excess of the Steady State Limit within 30 minutes.
- 2. verify that the QUADRANT POWER TILT is within its Transient Limit within_2_hours after exceeding the Transient Limit or reduce THERMAL POWER to less than 60% ot THERMAL POWER allowable for the reactor coolant pump combination within the next 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and ACTION C 4 reduce the High Flux Trip Setpoint to < 65.5% of THERMAL POWER allowable for the reactor coolant pump combination within the S Fhours3 SR 3.2.4.1 3. Identify and correct the cause of the out of limit condition prior to increasing THERMAL POWER; subsequent POWER OPERATION above 60%
of THERMAL POWER allowable for the reactor coolant pump combina.
tion may proceed provided that the QUADRANT POWER TILT is verified within its Steady State Limit at least once per hour for 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> or until verified acceptable at 95% or greater RATED THERMAL POWER
- c. With the QUADRANT POWER TILT determined to exceed the Transient Limit but less than the Maximum Limit provided in the CORE OPERATING LIMITS REPORT, due to causes other than the misalignment of either a safety, ACTION C 4 regulating or axial power shaping rod:
- 1. Reduce THERMAL POWER to less than 60% of THERMAL POWER allowable for the reactor coolant pump combination within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and reducie the High Flux Trip Setpoint to < 65.5% of THERMAL POWER allowable for the reactor coolant pump combination within the 1=0 -- LO3 TR 3.2.4.1 2. Identify and correct the cause of the out of limit condition prio r.
to increasing THERMAL POWER; subsequent POWER OPERATION above 60%
of THERMAL POWER allowable for the reactor coolant pump combina-tion may proceed provided that the QUADRANT POWER TILT is verified within its Steady State Limit at least once per hour for 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> or until verified at 95% or greater RATED THERMAL POWER.
Add proposed ACTION D M*0 144 DAVIS-BESSE. UNIT 1 314 2-10 Amendment No. fZ3;,;f.,
Page 2 of 3 Attachment 1, Volume 7, Rev. 0, Page 79 of 132
Attachment 1, Volume 7, Rev. 0, Page 80 of 132 ITS 3.2.4 ITS POWER DISTRIBUTION LIMITS LIMITING CONDITION FOR OPERATION (Continued)
ACTION: (Continued)
ACTION D d. With the QUADRANT POWER TILT determined to exceed the Maximum Limit provided in the CORE OPERATING LIMITS REPORT, reduce THERMAL POWER to ýof RATED THERMAL POWER within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />.
SURVEILLANCE REQUIREMENTS SR 3,2.4.1 4.2.4 The QUADRANT POWER TILT shall be determined to be < the Steady State Limits provided in the CORE OP RTING LIMITS REPORT at least once every 20) 7das durino peration above of RATED THERMPAL POWER except w enn shee L01 QUADRANT POWER T/T alarm is inopera-e. then the QUADRANT POWER/TILT shall Lbe c a l c u l a t e d a 0l e a t o n c e r 12 . hrbus .
pe - a DAVIS-BESSE. UNIT 1 3/4 2-11 Amendment No. ;23.144 (Next Page is 3/4 2-13)
Page 3 of 3 Attachment 1, Volume 7, Rev. 0, Page 80 of 132
Attachment 1, Volume 7, Rev. 0, Page 81 of 132 DISCUSSION OF CHANGES ITS 3.2.4, QUADRANT POWER TILT (QPT)
ADMINISTRATIVE CHANGES A01 In the conversion of the Davis-Besse 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-1430, Rev. 3.1, "Standard Technical Specifications-Babcock and Wilcox Plants" (ISTS).
These changes are designated as administrative changes and are acceptable because they do not result in technical changes to the CTS.
A02 The Applicability of CTS 3.2.4 is modified by footnote
- stating "See Special Test Exception 3.10.1." ITS 3.2.4 Applicability does not contain the footnote or a reference to the Special Test Exception.
The purpose of the CTS 3.2.4 footnote
- reference is to alert the user that a Special Test Exception exists which may modify the Applicability of the Specification. It is an ITS convention to not include these types of footnotes or cross-references. This change is designated as an administrative change since it does not result in technical changes to the CTS.
A03 CTS 3.2.4 Action a.1 .a states that with QPT determined to exceed the Steady State Limit but less than or equal to the Transient Limit within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> to reduce the QPT to within its Steady State Limit. ITS 3.2.4 does not contain a Required Action stating QPT must be reduced to within its limit.
This change is acceptable because the technical requirements have not changed. Restoration of compliance with the LCO is always an available Required Action and it is the convention in the ITS to not state such "restore" options explicitly unless it is the only action or is required for clarity. This change is designated as an administrative change since it does not result in technical changes to the CTS.
MORE RESTRICTIVE CHANGES M01 CTS 3.2.4 Action a.2, Action b.2, and Action c.1 do not provide any default actions to exit the Applicability of the Specification if any of the Required Actions are not met. If those actions are not complete, CTS 3.0.3 would be entered requiring entry into Hot Standby (MODE 3) within 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br />. However, since the Applicability of CTS 3.2.3 is MODE 1 with THERMAL POWER > 15% RTP, the power reduction would only be to 15% RTP. ITS 3.2.4 ACTION D requires a THERMAL POWER reduction to < 20% RTP within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. This changes the CTS by requiring THERMAL POWER to be reduced to outside of the Applicability of the Specification from 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br /> to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. The change from 15% RTP to 20% RTP is discussed in DOC L01.
The purpose of requiring a reduction of THERMAL POWER is to place the plant in a condition where the requirements for QPT limits are not required. This change is acceptable because it provides an adequate period of time to correct the condition or be in a MODE in which the requirement does not apply. The Davis-Besse Page 1 of 5 Attachment 1, Volume 7, Rev. 0, Page 81 of 132
Attachment 1, Volume 7, Rev. 0, Page 82 of 132 DISCUSSION OF CHANGES ITS 3.2.4, QUADRANT POWER TILT (QPT)
Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is reasonable for reaching < 20 % RTP from full power in an orderly manner and without challenging unit systems. This change has been designated as more restrictive because it reduces the Completion Time to be outside of the Applicability of the Specification.
RELOCATED SPECIFICATIONS None REMOVED DETAIL CHANGES None LESS RESTRICTIVE CHANGES L01 (Category 2 - Relaxation of Applicability) CTS 3.2.4 is applicable in MODE 1 above 15% RTP. In addition, due to this Applicability, when the QPT is exceeding the Maximum Limit in the COLR, CTS 3.2.4 Action d requires a power reduction to < 15% RTP. Furthermore, CTS 4.2.4, the QPT Surveillance, is required when above 15% RTP. ITS 3.2.4 is applicable in MODE 1 when > 20%
RTP. Under similar conditions as in the CTS, ITS 3.2.4 ACTION D requires a reduction in power to < 20% RTP. Furthermore, ITS SR 3.2.4.1 is applicable when > 20% RTP. This changes the CTS by changing the Applicability of the QPT requirement from > 15% RTP to >20% RTP.
The purpose of the QPT limits is to assist in preventing the core power distribution from exceeding the design limits. This change is acceptable because the proposed 20% RTP Applicability limit will continue to ensure the core power distribution will not exceed the design limits. At power levels at or below 20%
RTP, tilt limitations are unnecessary. Since tilt is a measure of the increase in quadrant radial power relative to average quadrant power, large tilts can result from small deviations in core quadrant powers when the reactor is operating at low power. Requiring tilt monitoring at 20% RTP provides a conservatively low power limit for Applicability. Operation below 20% RTP with a QPT up to 20% is acceptable because the resulting maximum linear heat rate (LHR) is not high enough to cause violation of the loss of coolant LHR limit (FQ limit) or the initial condition departure from nucleate boiling allowable peaking factor (F. H limit) during accidents initiated from this power level. Furthermore, the proposed power level of 20% RTP is large enough to obtain more meaningful QPT indications using the Incore Detector System without compromising safety. This change is designated as less restrictive because the ITS LCO requirements are applicable in fewer operating conditions than in the CTS.
L02 (Category 3- Relaxation of Completion Time) CTS 3.2.4 Action a.1.b, which applies when QPT is determined to exceed the Steady State Limit but less than or equal to the Transient Limit, requires a reduction of THERMAL POWER within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and also requires a reduction of the High Flux trip setpoint and the Flux-Davis-Besse Page 2 of 5 Attachment 1, Volume 7, Rev. 0, Page 82 of 132
Attachment 1, Volume 7, Rev. 0, Page 83 of 132 DISCUSSION OF CHANGES ITS 3.2.4, QUADRANT POWER TILT (QPT)
AFlux-Flow trip setpoint at least 2% for each 1% of QPT in excess of the Steady State Limit within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. CTS 3.2.4 Action a.2 requires QPT to be within it Steady State limit within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Under the same conditions in the ITS, ITS 3.2.4 ACTION A requires the reduction in THERMAL POWER and the trip setpoints but the Completion Time for reducing the trip setpoints has been extended to 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> or provides the option to perform ITS SR 3.2.5.1 (Verify Fa and FA Hare within limits by using the Incore Detector System to obtain a power distribution map) once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, and requires restoration of QPT to within limits within 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 extending the Completion Time to reduce the trip setpoints from "4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />" to "10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br />" and providing an option to verify F0 and F. H are within their limits once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for the first 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> instead of reducing THERMAL POWER and the trip setpoints.
The purpose of CTS 3.2.4 Action a.1 .b is provide appropriate compensatory measures for QPT greater than that the Steady State Limit but less than or equal to the Transient Limit. 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. This includes a reasonable time for repairs or replacement, and the low probability of a DBA occurring during the allowed Completion Time. This changes the CTS by extending the Completion Time to reduce the trip setpoints and provides an option to verify F0 and F. H are within their limits once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> instead of reducing THERMAL POWER and the trip setpoint. The steady state limit specified in the COLR provides an allowance for QPT that may occur during normal operation. A peaking increase to accommodate QPTs up to the steady state limit is allowed by the regulating rod insertion limits of LCO 3.2.1 and the AXIAL POWER IMBALANCE limits of LCO 3.2.3. Operation with QPT greater than the steady state limit specified in the COLR potentially violates the LOCA LHR limits (F0 limits), or loss of flow accident DNB peaking limits (F. H limits), or both. Verification that FQ and FH. are within their limits ensures that operation with QPT greater than the steady state limit does not violate the ECCS or 95/95 DNB criteria. The required Completion Time of once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is a reasonable amount of time to allow the operator to obtain a power distribution map and to verify the power peaking factors. Repeating SR 3.2.5.1 every 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is a reasonable Frequency at which to ensure that continued verification of the power peaking factors is obtained as core conditions that influence QPT change. The safety analysis has shown that a conservative corrective action is to reduce THERMAL POWER by 2% RTP or more from the ALLOWABLE THERMAL POWER for each 1% of QPT in excess of the steady state limit. This action limits the local LHR to a value corresponding to steady state operation, thereby reducing it to a value within the assumed accident initial condition limits.
The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is reasonable, based on limiting the potential for xenon redistribution, the low probability of an accident occurring, and the steps required to complete the Required Action. If QPT can be reduced to less than or equal to the steady state limit in < 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, the reactor may return to normal operation without undergoing a power reduction. Significant radial xenon redistribution does not occur within this amount of time. The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> after the last performance of SR 3.2.5.1 allows reduction of THERMAL POWER in the event the operators cannot or choose not to continue Davis-Besse Page 3 of 5 Attachment 1, Volume 7, Rev. 0, Page 83 of 132
Attachment 1, Volume 7, Rev. 0, Page 84 of 132 DISCUSSION OF CHANGES ITS 3.2.4, QUADRANT POWER TILT (QPT) to perform SR 3.2.5.1 as required by Required Action A.1.1. Power operation is allowed to continue if THERMAL POWER is reduced in accordance with Required Action A.1.2.1. The same reduction (i.e., 2% RTP or more) is also applicable to the High Flux trip setpoint and the Flux-AFlux-Flow trip setpoint, for each 1% of QPT in excess of the steady state limit. This reduction maintains both core protection and an OPERABILITY margin at the reduced THERMAL POWER level similar to that at RTP. The required Completion Time of 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> is reasonable based on the need to limit the potentially adverse xenon redistribution, the low probability of an accident occurring while operating out of specification, and the number of steps required to complete the Required Action.
Although the actions directed by Required Action A.1.2.1 restore margins, ifthe source of the QPT is not established and corrected, it is prudent to establish increased margins. A required Completion Time of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to reduce QPT to less than the steady state limit is a reasonable time for investigation and corrective measures. This change is designated as less restrictive because additional time is allowed to reduce the trip setpoints and an option has been provided to verify FQ and FH. are within their limits once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />.
L03 (Category3 - Relaxation of Completion Time) CTS 3.2.4 Action a. 1 and a.2 provide Actions for when QPT is determined to exceed the Steady State Limit but less than or equal to the Transient Limit. CTS 3.2.4 Action b.1 and b.2 provide Actions for when QPT is determined to exceed the Transient Limit but less than or equal to the Maximum Limit. CTS 3.2.4 Action b.1 and b.2 provide Actions for when QPT is determined to exceed the Transient Limit but less than or equal to the Maximum Limit due to misalignment of either a safety, regulating or axial power shaping rod. When these Actions are not met CTS 3.2.4 Action a.2 and CTS 3.2.4 Action b.2 both require a reduction to less than 60% of the ALLOWABLE THERMAL POWER within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and a reduction in the High Flux trip setpint to < 65.5% within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. CTS 3.2.4 Action c.1 provide Actions for when QPT is determined to exceed the Transient Limit but less than the Maximum Limit due to causes other than the misalignment of either a safety, regulating or axial power shaping rod. Under the same conditions, ITS 3.2.4 ACTION C specifies the same requirements however the Completion Time to reduce the High Flux trip setpoint has been extended to 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br />. This changes the CTS by extending the Completion Time from "4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />" to "10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br />."
The purpose of CTS 3.2.4 Actions is to provide appropriate compensatory measures for QPT greater than the specified limits. This change is acceptable because the Completion Time is consistent with safe operation under the specified Condition, considering a reasonable time for restoration and the low probability of a DBA occurring during the allowed Completion Time. This changes the CTS by extending the Completion Time to reduce the trip setpoints of the High Flux channels. Under the specified conditions a power reduction to
< 60% RTP provides conservative protection from increased peaking due to xenon redistribution. The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is reasonable to allow the operator to reduce THERMAL POWER to < 60% of ALLOWABLE THERMAL POWER without challenging plant systems. Reduction of the High Flux trip setpoint to - 65.5% of ALLOWABLE THERMAL POWER after THERMAL POWER has been reduced to < 60% of ALLOWABLE THERMAL POWER maintains both core protection and OPERABILITY margin at reduced Davis-Besse Page 4 of 5 Attachment 1, Volume 7, Rev. 0, Page 84 of 132
Attachment 1, Volume 7, Rev. 0, Page 85 of 132 DISCUSSION OF CHANGES ITS 3.2.4, QUADRANT POWER TILT (QPT) power similar to that at full power. The required Completion Time of 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> allows the operator sufficient time to reset the trip setpoint and is reasonable based on the number of steps required to complete the action. This change is designated as less restrictive because additional time is allowed to reduce the trip setpoints.
L04 (Category 7- Relaxation Of Surveillance Frequency - Non-24 Month Type Change) CTS 4.2.4 requires the QPT to be verified to be within limit every 7 days when the QPT alarm is OPERABLE and requires the verification every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> when the QPT alarm is inoperable. ITS SR 3.2.4.1 requires verification that QPT is within limit every 7 days. This changes the CTS by eliminating the requirement to verify QPT more frequently when the QPT alarm is inoperable.
The purpose of CTS 4.2.4 is to periodically verify that QPT is within limit. This change is acceptable because increasing the frequency of QPT verification when the QPT alarm is inoperable is unnecessary. The inoperability of the alarm does not increase the probability that QPT is outside its limit. The routine 7 day Frequency (ITS SR 3.2.4.1) continues to ensure QPT is within the limit.
Furthermore, the QPT alarm is for indication only. Its use is not credited in any of the safety analyses. Thus, any response determined necessary by plant personnel due to an inoperable alarm 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 the ITS than under the CTS.
Davis-Besse Page 5 of 5 Attachment 1, Volume 7, Rev. 0, Page 85 of 132
Attachment 1, Volume 7, Rev. 0, Page 86 of 132 Improved Standard Technical Specifications (ISTS) Markup and Justification for Deviations (JFDs)
Attachment 1, Volume 7, Rev. 0, Page 86 of 132
Attachment 1, Volume 7, Rev. 0, Page 87 of 132 CTS QPT 3.24 3.2 POWER DISTRIBUTION LIMITS 3.2.4 QUADRANT POWER TILT'(QPT) 3.2.4 LCO 3.2.4 QPT shall be maintained less than or equal to the steady state limits specified in the COLR.
APPLICABILITY: MODE 1 with THERMAL POWER > j.20F/o RTP. 0 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME 3.2.4 Action a.1 A. QPT greater than the A.1.1 Perform SR 3.2.5.1. Once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> steady state limit and less than or equal to the OR transient limit.
A.1.2.1 Reduce THERMAL 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> POWER Ž 2% RTP from the ALLOWABLE OR THERMAL POWER for each 1% of QPT greater 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> after last than the steady state limit, performance of 0
AND A.1.2.2 Reduce nuclerr 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> tri p setpo int a nd 1nuc ea r/
overpoe/ based onL_ 0 flow an* AXIAýL P01 R I -*Fu-*~xFo IMBAL NCE/trip setpoint
>! 2% RTP from the ALLOWABLE THERMAL POWER for each 1% of QPT greater than the steady state limit.
AND BWOG STS 3.2.4-1 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 87 of 132
Attachment 1, Volume 7, Rev. 0, Page 88 of 132 QPT 3.2.4 iO CTS ACTIONS (continued)
CONDITION REQUIRED ACTION COMPLETION TIME 3.2.4 Action a.2 A.2 Restore QPT to less than or 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from equal to the steady state discovery of failure to limit. meet the LCO 3.2.4 Action b.1, B. QPT greater than the B.1 Reduce THERMAL 30 minutes 3.2.4 Action b.2 transient limit and less POWER > 2% RTP from than or equal to the ALLOWABLE THERMAL maximum limit due to POWER for each 1% of misalignment of a QPT greater than the CONTROL ROD or an steady state limit.
APSR.
AND B.2 RestoreQPT to less than or 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> equal to the transient limit.
+/-
. 3.2.4 Action a.2. C.
3.2.4 Action b.2 Required Action and associated Completion Time of Condition A or B C.1 Reduce THERMAL POWER to < 60% of the ALLOWABLE THERMAL 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> not met. POWER.
AND E
C.2 Reduce l i
10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> 0
or/ trip setpoint to <_65.5% of oRI the ALLOWABLE THERMAL POWER.
0 i i i 3.2.4 Action c. 1 QPT greater than the D.1 Reduce TI ERMAL 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> transient limit and less POWER tc < 60% of the than or equal to the ALLOWABE THERMAL maximum limit due to POWER.
causes other than the 3 AND\
misalignment of either CONTROL ROD or APSR. D.2 Reduce nuclear overpower 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> trip setpoint l.o ___
65.5% of the ALLOWA.BLE THERMAL PR WER.
BWOG STS 3.2.4-2 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 88 of 132
Attachment 1, Volume 7, Rev. 0, Page 89 of 132 QPT 3.2.4 O CTS ACTIONS (continued)
CONDITION REQUIRED ACTION COMPLETION TIME DOC M01 Required Action and Reduce THERMAL 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> 03 associated Completion POWER to < 20p%RTP.
Time for Condition C /
oFr- not met.
OR 3.2.4 Action d _ greater than the QPT F.1 Reduce TIERMAL 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> maximum limit. \ POWER tol\[201% RTP. 0 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY 4.2.4, SR 3.2.4.1 Verify QPT is within limits as specified in the COLR. 7 days 3.2.4 Action a.3.
3.2.4 Action b.3
--Note AND Only required to be performed if both Condition C was entered and THERMAL When QPT has 0
POWER is > 60% of ALLOWABLE THERMAL POWER been restored to less than or equal once every hour for 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> to the steady state coscutiv*
0 verified acceptable at
> 95% RTP BWOG STS 3.2.4-3 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 89 of 132
Attachment 1, Volume 7, Rev. 0, Page 90 of 132 JUSTIFICATION FOR DEVIATIONS ITS 3.2.4, QUADRANT POWER TILT (QPT)
- 1. The brackets have been removed and the proper plant specific information/value has been provided.
- 2. Editorial changes made with no change in intent.
- 3. The Required Actions and associated Completion Times in ISTS 3.2.4 ACTION C and ACTION D are equivalent. Therefore, the Condition of ISTS 3.2.4 ACTION D has been merged with the Condition of ISTS 3.2.4 ACTION C. The Required Actions and associated Completion Times in ISTS 3.2.4 ACTION E and ACTION F are equivalent. Therefore, the Condition of ISTS 3.2.4 ACTION E (ITS 3.2.4 ACTION D) has been merged with the Condition of ISTS 3.2.4 ACTION F. This change is consistent with the Writer's Guide for Plant-Specific Improved Technical Specifications, TSTF-GG-05-01, Section 4.1.6. Subsequent Conditions and Required Actions have been renumbered, as applicable.
- 4. A Note has been added to the second Frequency of ISTS SR 3.2.4.1. The Note states that "Only required to be performed if both Condition C was entered and THERMAL POWER is 60% of ALLOWABLE THERMAL POWER. This allowance is consistent with CTS 3.2.4 Action a.3 and CTS 3.2.4 Action b.3 and the description of the SR in the Bases.
- 5. Changes are made which reflect the plant specific nomenclature.
Davis-Besse Page 1 of 1 Attachment 1, Volume 7, Rev. 0, Page 90 of 132
Attachment 1, Volume 7, Rev. 0, Page 91 of 132 Improved Standard Technical Specifications (ISTS) Bases Markup and Justification for Deviations (JFDs)
Attachment 1, Volume 7, Rev. 0, Page 91 of 132
Attachment 1, Volume 7, Rev. 0, Page 92 of 132 QPT B 3.2A B 3.2 POWER DISTRIBUTION LIMITS B 3.2.4 QUADRANT POWER TILT (QPT)
BASES BACKGROUND This LCO is required to limit the core power distribution based on accident initial condition criteria.
The power density at any point in the core must be limited to maintain specified acceptable fuel design limits, including limits that preserve the criteria specified in 1:0.CFR 50.46 (Ref. 1). Together, LCO 3.2.1, "Regulating Rod Insertion Limits," LCO 3.2.2, "AXIAL POWER SHAPING ROD (APSR) Insertion Limits," LCO 3.2.3, "AXIAL POWER IMBALANCE Operating Limits," and LCO 3.2.4, "QUADRANT POWER TILT (QPT),"
provide limits on control component operation and on monitored process variables to ensure that the core operates within the FoP5 and F. H limits given in the COLR. Operation within the FaM limits given in the COLR rate(L linerheat prevents power peaks that exceed the loss of coolant accident (LOCA) limits derived by Emergency Core Cooling Systems (ECCS) analysis.
Operation within the F. H limits given in the COLR prevents departure from nucleate boiling (DNB) during a loss of forced reactor coolant flow accident.
This LCO is required to limit fuel cladding failures that breach the primary fission product barrier and release fission products to the reactor coolant in the event of a LOCA, loss of forced reactor coolant flow, or other accident requiring termination by a Reactor Protection System trip function. This LCO limits the amount of damage to the fuel cladding during an accident by maintaining the validity of the assumptions used in the safety analysis related to the initial power distribution and reactivity.
Fuel cladding failure during a postulated LOCA is limited by restricting the maximum linear heat rate (LHR) so that the peak cladding temperature does not exceed 2200°F (Ref. 2). Peak cladding temperatures > 2200°F cause severe cladding failure by oxidation due to a Zircaloy water reaction. Other criteria must also be met (e.g.., maximum cladding oxidation, maximum hydrogen generation, coolable geometry, and long term cooling). However, peak cladding temperature is usually most limiting.
BWOG STS B 3.2.4-1 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 92 of 132
Attachment 1, Volume 7, Rev. 0, Page 93 of 132 QPT B.3.2.4 BASES BACKGROUND (continued)
Proximity to the DNB condition is expressed by the departure from nucleate boiling ratio (DNBR), defined as the ratio of the cladding surface
- heat flux required to cause DNB to the actual cladding surface heat flux.
The minimum DNBR value during both normal operation and anticipated transients is limited to the DNBR tcorrelation limit for the particular fuel design in use, and is accepted as an appropriate margin to DNB. The DNBR correlation limit ensures that there is at least 95% probability at the 95% confidence level (the 95/95 DNB criterion) that the hot fuel rod in the core does not experience DNB.
The measurement system independent limits on QPT are determined directly by the reload safety evaluation analysis without adjustment for measurement system error and uncertainty. Operation beyond these limits could invalidate core power distribution assumptions used in the Z~IJ accident analysis. The error adjusted maximum allowable r
-stpjits(measurement system dependent limits) for QPT are specified in the COLR.
0 APPLICABLE The fuel cladding must not sustain damage as a result of normal SAFETY operation (Condition 1) and anticipated operational occurrences ANALYSES (Condition 2). The LCOs based on power distribution (LCO 3.2.1, LCO 3.2.2, LCO 3.2.3, and LCO 3.2.4) preclude core power distributions that violate the following fuel design criteria:
- a. During a ar:g rea LOCA, the peak cladding temperature must not exceed 2200'F (Ref.. 2 0
- b. During a loss of forced reactor coolant flow accident, there must be at least 95% probability at the 95% confidence level (the 95/95 DNB criterion) that the hot fuel rod in the core does not experience a DNB conditionm.J NR INýSEýRT 1 QPT is one of the process variables that characterize and control the three dimensional power distribution of the reactor core.
Fuel cladding damage does not occur when the core is operated outside this LCO during normal operation. However, fuel cladding damage could result if an accident occurs with simultaneous violation of one or more of the LCOs governing the core power distribution. Changes in the power distribution can cause increased power peaking and correspondingly increased local LHRs.
BWVOG STS B 3.2.4-2 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 93 of 132
Attachment 1, Volume 7, Rev. 0, Page 94 of 132 B 3.2.4 S INSERT 1
- c. During an ejected rod accident, the fission energy input to the fuel must not exceed 280 cal/gm (Ref. 3); and
- d. The CONTROL RODS must be capable of shutting down the reactor with a minimum required SDM with the highest worth CONTROL ROD stuck fully withdrawn (Ref. 4).
Insert Page B 3.2.4-2 Attachment 1, Volume 7, Rev. 0, Page 94 of 132
Attachment 1, Volume 7, Rev. 0, Page 95 of 132 OPT
,B 3.2.4 BASES APPLICABLE SAFETY ANALYSES (continued)
The dependence of the core power distribution on burnup, regulating rod insertion, APSR position, and spatial xenon distribution is taken into account during the reload safety evaluation analysis. An allowance for QPT is accommodated in the analysis and resultant LCO limits. The increase in peaking taken for QPT is developed from a database of full core power distribution calculations (Ref . The calculations consist of simulations of many power distributions with tilt causing mechanisms (e.g., dropped or misaligned CONTROL RODS, broken APSR fingers fully inserted, misloaded assemblies, and burnup gradients). An increase of < 2% peak power per 1% OPT is supported by the analysis, therefore a value of 2% peak power increase per 1% OPT is used to bound peak power increases due to OPT.
Operation at the AXIAL POWER IMBALANCE or rod insertion limits must be interpreted as operating the core at the maximum allowable FQM) or Fr H peaking factors for accident initial conditions with the allowed QPT present.
QPT satisfies Criterion 2 of 10 CFR 50.36(c)(2)(ii).
LCO The power distribution LCO limits have been established based on correlations between power peaking and easily measured process variables: regulating rod position, APSR position, AXIAL POWER IMBALANCE, and QPT. The regulating rod insertion limits and the AXIAL POWER IMBALANCE boundaries contained in the COLR represent the measurement system independent limits at which the core power distribution either exceeds the LOCA LHR limits or causes a reduction in DNBR below the safety limit during a loss of flow accident with the allowable QPT present and with an APSR position consistent with the limitations on APSR withdrawal determined by the fuel cycle design and specified by LCO 3.2.2.
Operat,*on beyond the power distribution based LCO lI nits for the corresp nding allowable THERMAL POWER and simLltaneous occurren e of one of a LOCA, loss of forced reactor co lant flow accident, (7 or ejectec rod accident has an cceptably low probabilit. Therefore, if these LCC limits are violated, a short time is allowed for .orrective action before a si nificant power reduct'on is required.
BVWOG STS B 3.2.4-3 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 95 of 132
Attachment 1, Volume 7, Rev. 0, Page 96 of 132 QPT B 3.2.4 BASES LCO (continued)
I The Imaximum aJlowab1 setpoints for steady state, transient, and limits maximum limits for QPT applicable for the full syyx etrical! Incore Detector System minimumcore Detector ý,yst em, -and Ex'ore ýUetector I
- -m-are provided; the setppigts-are givenj in the COLR. The setpnts Incore Detector System for th~ ree ems are derived by adjustment of the measurement system independent QPT limits *given e COLR to allow for system
.observability and instrumentation errors.
Actual aýarm setpoints implenkented in the plant may b` more restrictive than the maximum allowable stpoint values to allow foi additional
,conservati. m between the actual alarm setpoint and the i easurement 0
system ind'\pendent limit.
It is deE,\irable for an operator to retain the ability to operate the reactor when a QPT exists. In certai instances, operation of \he reactor with a QPT ma\' be helpful or necesE4ary to discover the cause, of the QPT. The combinatlon of power level resttriction with QPT in each equired Action 0
statement\restricts the local LHR to a safe level, allowing\ movement through the specified applicabilit conditions in the exception to Specificatidp 3.0.3.
APPLICABILITY In MODE 1, the limits on QPT must be maintained when THERMAL POWER is > 20% RTP to prevent the core power distribution from exceeding the design limits. The minimum power level of 20% RTP is large enough to obtain meaningful QPT indications without compromising safety. Operation at or below 20% RTP with QPT up to 20% is acceptable because the resulting maximum LHR is not high enough to cause violation of the LOCA LHR limit (FoM- limit) or the initial condition DNB allowable peaking limit (FAl limit) during accidents initiated from this 0
power level.
In MODE 2, the combination of QPT with maximum ALLOWABLE THERMAL POWER level does not result in LHRs sufficiently large to violate the fuel design limits, and therefore, applicability in this MODE is not required. Although not specifically addressed in the LCO, QPTs
> 20% in MODE 1 with THERMAL POWER < 20% RTP are allowed for the same reason.
BWOG STS B 3.2.4-4 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 96 of 132
Attachment 1, Volume 7, Rev. 0, Page 97 of 132 QPT B 3.2.4 BASES APPLICABILITY (continued)
In MODES 3, 4, 5, and 6, this LCOiis not applicable, because the reactor is not generating THERMAL POWER and QPT is indeterminate.
In MODE 1,, it may be necessary to suspend the OPT limits during PHYSICS TESTS per LCO 3.1.8, "PHYSICS TESTS Exceptions -
MODE 1." Suspension of these limits is permissible because the reactor protection criteria are maintained by .the remaining LCOs governing the three dimensional power distribution and by the Surveillances required by LCO 3.1.8.
ACTIONS A.1.1 The steady state limit specified in the COLR provides an allowance for QPT that may occur during normal operation. A peaking increase to accommodate QPTs up to the steady state limit is allowed by the regulating rod insertion limits of LCO 3.2.1 and the AXIAL POWER IMBALANCE limits of LCO 3.2.3.
Operation with QPT greater than the steady state limit specified in the COLR potentially violates the LOCA LHR limits (Fo[2limits), or loss of flow accident DNB peaking limits (F,% limits), or both. For verification that FQM2) and F',H are within their specified limits, SR nis . I (Q performed using the Incore Detector System to obtain a three dimensional power distribution map. Verification that FQ 2-) and F',H are within their limits ensures that operation with QPT greater than the steady state limit does not violate the ECCS or 95/95 DNB criteria. The required Completion Time of once per 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is a reasonable amount of time to allow the operator to obtain a power distribution map and to verify the power peaking factors. Repeating SR 3.2.5.1 every 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is a reasonable Frequency at which to ensure that continued verification of the power peaking factors is obtained as core conditions that influence OPT change.
A.1.2.1 The safety analysis has shown that a conservative corrective action is to reduce THERMAL POWER by 2% RTP or more from the ALLOWABLE THERMAL POWER for each 1% of QPT in excess of the steady state limit. This action limits the local LHR to a value corresponding to steady state operation, thereby reducing it to a value within the assumed BWOG STS B 3.2.4-5 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 97 of 132
Attachment 1, Volume 7, Rev. 0, Page 98 of 132 QPT B 3.2.4 BASES ACTIONS '(continued) accident initialcondition limits. The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is reasonable, based on limiting the potential for xenon redistribution, the low probability of an accident occurring, and the steps required to complete the Required Action.
If QPT can be reduced to less than or equal to the steady state limit in
< 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, the reactor may return to normal operation without undergoing a power reduction. Significant radial xenon redistribution does not occur within this amount of time.
[ The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> after the last performance of Z rx16.1 allows reduction of THERMAL POWER in the event the operators cannot or choose not to continue to perform SRM as required by Required Action A.1.1.
A.1.2.2 Power operation is allowed to continue if THERMAL POWER is reduced High Flux in accordance with Required Action A.1.2.1. The same reduction (i.e.,
2% RTP or more) is also applicable to ther-nuclearo-verpoweritrip setpoint and the nuclear; verpower ba'sed on Reactor C/oolant System (RCS) flow 0 andLAXIAL PO\_ R IMBAIJANCE trip setpoint, for each 1% of QPT in
_ FIux-*-FIow excess of the steady state limit. This reduction maintains both core protection and-an OPERABILITY margin at the reduced THERMAL POWER level similar to that at RTP. The required Completion Time of 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> is reasonable based on the need to limit the potentially adverse xenon redistribution, the low probability of an accident occurring while operating out of specification, and the number of steps required to complete the Required Action.
from discovery of A.2 failure to meet the LCO Although the actions directed by Required Action A.1.2.1 restore margins, if the source of the QPT is not established and corrected, it is prudent to establish increased margins. A required Completion Time of 24 hourto (o reduce QPT to less than the steady state limit is a reasonable time for investigation and corrective measures.
BWOG STS B 3.2.4-6 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 98 of 132
Attachment 1, Volume 7, Rev. 0, Page 99 of 132 QPT B 3.2.4 BASES ACTIONS (continued) 1B.1 If QPT exceeds the transient limit but is equal .to or less than the maximum limit due to a misaligned CONTROL ROD or APSR, then power
,operation is allowed to continue if the THERMAL POWER is reduced
- 2% RTP or more from the ALLOWABLE THERMAL POWER for each 1%
of QPT in excess of the steady state limit. Thus, the traien imi isthe maxim (um upper bound within which the 2% for 1% power reduction rule may be applied, but only for QPTs caused by CONTROL ROD or APSR misalignment. The required Completion Time of 30 minutes ensures that the operator completes the THERMAL POWER reduction before significant xenon redistribution occurs.
B.2 When a misaligned CONTROL ROD or APSR occurs, a local xenon redistribution may occur. The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> allows the operator sufficient time to relatch or realign a CONTROL ROD or APSR, but is short enough to limit xenon redistribution so that large increases in the local LHR do not occur due to xenon redistribution resulting from the QPT. or or ift QPT is greater than the transient limit and less than or equal to the maximum limit due to t" 1 C,. m salignment of a CONTROL ROD o*r an APSR any is I e Required Action and associated Completion Time of Condition A orB 'enot met, afurther power reduction is required. Power reduction Power reduction to 60% of the to < 60% RTP provides conservative protection from increased peaking ALLOWABLE THERMAL POWER isa conservative method of limiting the maximum core LHR due to xenon redistribution. The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is reasonable to allow the operator to reduce THERMAL POWER to < 60%
0 for OPTs up to the maximum limit,. fALW BETEM L O E Mhu challenging plant ln systems.
Although the power reduction is of ALLOWABLE THERMAL POWER without based on the correlation used in Required Actions A.1.2.1 and B.1, the database for a power peaking increase as a function of OPT is C.2 less extensive for tilt mechanisms High Flux other than misaligned CONTROL RODS and APSRs. Because greater uncertainty in the potential power peaking increase exists Reduction of the nuclearý rower!trip setpoint to -<65.5% of ALLOWABLE THERMAL POWER after THERMAL POWER has been 0 with the less extensive database, reduced to < 60% of ALLOWABLE THERMAL POWER maintains both a more conservative action is core protection and OPERABILITY margin at reduced power similar to taken when the tilt is caused by a mechanism other than a that at full power. The required Completion Time of 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> allows the misaligned CONTROL ROD or operator sufficient time to reset the trip setpoint and is reasonable based on peratinexperience.
1 the number of steps required to complete the Required Action 0
BWOG STS B 3.2.4-7 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 99 of 132
Attachment 1, Volume 7, Rev. 0, Page 100 of 132 QPT B 3.2.4 BASES ACTIONS *(continued)
- D.1 Power reduction to 60% of heALLOWABLE THER AL POWER is a conser ative method of limitng the maximum core L R forQPTs up to 20%. ,Although the power reduction is based on the correlation used in Required Actions A.1.2.1 an B.1, the database for a ower peaking increas, as a function of QP is less extensive fortilt echanisms other than mialigned CONTROL ODS and APSRs. Beca se greater 0 uncertail ty in the potential po r peaking increase exi ts with the less extensiv database, a more ck nservative action is take when the tilt is caused b a mechanism other than a misaligned CON1 ROL ROD or APSR. T e required Completi n Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> allow the operator to reduce TI- ERMAL POWER to 60% of the ALLOWABLE THERMAL POWER v thout challenging ph nt systems.
2 Reduction of the nuclear ov rpower trip setpoint to -<(5.5% of the ALLOW\AABLE THERMAL PCWER after THERMAL P2WER has been 0
reduce,* o < 60% of the ALL WABLE THERMAL PON R maintains both corir protection and an o Ierating margin at reduce~i power similar to that at ful power. The requirei Completion Time of 10 `ours allows the operator - ufficient time to reset the trip setpoint and is re sonable based on operati g experience.
and associated Completion Time of ]n oo'for QPT is greater than the Fany maximum limit I tNe Required Action~f~r]Condition C oD not be n-etvytjtne T then ih reactor will coptinue in power the reactor must beC',mpleti brought to a MODE or operation with .ignificant OPT. Ei' her the power I vel has not been other specified condition nthi in reduced to cornply with the Requ'red Action or th nuclear overpower trip
..hi....chiv aply TorachitevLdes the es.no setpoint has r2ot been reduced w ithin the require Completion Time. To
\us status. THERMAL preclude risk/of fuel damage in -ny of these co ditions, THERMAL POWER must be reduced POWER be is r/duced further. Sr ecification 3.0.. normally requires a reduced to < 20% RTP within P 2r WE our.shutdown t MODE 3. Howe\er,, peration at 20% RTP allows the operator to investigate the cause of the QPT and to correct it. Local LHRs with a large QPT do not violate the fuel design limits at or below 20% RTP. The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is acceptable based on limiting the potential increase in local LHRs that could occur due to xenon redistribution with the QPT out of specification.
The maximum limit specified in the COLR is set as the upper bound within which power reduction to 60% of ALLOWABLE THERMAL POWER or power reduction of 2% from ALLOWABLE THERMAL POWER for each 1% of OPT (for misaligned CONTROL RODS only)I applies (Ref. 5). The maximum limit specified in the COLR is consistent with allowing power operation up to 60% of ALLOWABLE THERMAL POWER when OPT setpoints are exceeded. OPT in excess of the maximum limit can be an indication of a severe power distribution anomaly, and a power reduction to at most 20% RTP ensures local LHRs do not exceed allowable limits while the cause is
,being determined and corrected.
BVWJOG STS B 3.2.4-8 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 100 of 132
Attachment 1, Volume 7, Rev. 0, Page 101 of 132 QPT
'B 3.2.4 BASES ACTIONS (continued)
The ma imum limit of 20% QCT is set as the upper bound within which power reduction to 60% of AL LOWABLE THERMAL P WER or power (Ref. 4).\ of 2% for 1% (for m saligned CONTROL RO)S only) applies reducti The maxiium limit of 20% QPT is consistent with allow ng power operation \up to 60% of ALLO\AABLE THERMAL POWER when QPT setpoints re exceeded. QPT p excess of the maximun limit can be an indication iLf a severe power distribution anomaly, and a ower reduction to at most k0% RTP ensures loll I LHRs do not exceed a Ilowable limits while the cuse is being determi ed and corrected.
The require Completion Time o 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is reasonable tc allow the operator to ileduce THERMAL POWER to < 20% RTP witt out challenging plant systerrs.
SURVEILLANCE QPT can be monitored by 5T6\-the Incore n -xcor* cietector ;ystemm.
REQUIREMENTS The QPT e in s are derived from their corres on easuremen limits s s em independent limits by adjustment for system observability errors Incore Detector and instrumentation errors. Althoug they may be baseL on the same System [measuremet system independent lin.!', the setpoints for t. e different systems are 'rot identical because of differences in the errorf, applicable for these syste s. For QPT measurements using the Incore Detector System, the inimum lncore Detecto stem consists ot OPERABLE d et ect orýofg u re'dýasfolw:
detectors per qu5rq*ant a. Two sets of four detecto*i shall lie in each core If. Each set of detec.rs shall lie in the sa. e axial plane. The twsets in the same core he f may lie in the same axial plane.
- b. Det-dtrs in the same pl shall have quarter co eadial symmetry.
Figure 3.2.4-2 (Minimum I core Detector System f r QPT Measurenent) depicts an ex- mple of this configuratio . The symmetric incore sytem for QPT uses tl? Incore Detector Systei as described above and is configured such ti at at least 75% of the detectors in each core quadrant are OPERABLE.
BWAOG STS B 3.2.4-9 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 101 of 132
Attachment 1, Volume 7, Rev. 0, Page 102 of 132 QPT B 3.2.4 BASES SURVEILLANCE REQUIREMENTS (continued)
SR 3.2.4.1 Checking the QPT indication every 7 days ensures that the operator can determine whetherithe plant computer software :and Incore Detector System inputs for monitoring QPT are functioning properly and takes into account other information and arms available to the operator in the control room. This procedure allows the QPT mechanisms, such as 0
xenon redistribution, burnup gradients, and CONTROL ROD drive mechanism malfunctions, which can cause slow development of a QPT, to be detected. Operating experience has confirmed the acceptability of a Surveillance Frequency of 7 days.
Following restoration of the QPT to within the steady state limit, operation at -- 95% RTP may proceed provided the QPT is determined to remain
(* within the steady state limit at the increased THERMAL POWER level. In once every case QPT exceeds the steady state limit for [iore than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or exceeds the transient limit (Condition AFA or[), the potential for xenon redistribution is greater. Therefore, the QPT is monitored [r 0
hour for 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> 12 consecu urly intervals- to determine whether the period of any 0 oscillation due to xenon redistribution causes the QPT to exceed the steady state limit again.
REFERENCES 1. 10CFR5 e.46.
'--U FSAR, !..3 Section 00
- 3. ANSI N18.2-1973, A rican National Standards Institute, August 6, 1973. 0 W-411.BAW 10122A, Rev. 1, May 1984.
0 0
BWOG STS B 3.2.4-10 Rev. 3.0, 03/31104 Attachment 1, Volume 7, Rev. 0, Page 102 of 132
0 , Volume 7, Rev. 0, Page 103 of 132
Attachment 1, Volume 7, Rev. 0, Page 104 of 132 JUSTIFICATION FOR DEVIATIONS ITS 3.2.4 BASES, QUADRANT POWER TILT (QPT)
- 1. These punctuation corrections have been made consistent with the Writer's Guide for the Improved Standard 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 3.2.4 Bases, LCO section provides a discussion that it is sometimes desirable to continue to operate the reactor when the QPT limit is not met, and describes why this is acceptable. This discussion has not been maintained in the Davis-Besse ITS Bases. The discussion is basically describing what is allowed for all LCO statements - that the LCO can be not met under certain circumstances as long as the associated ACTIONS are followed. The ISTS ACTIONS Bases provides the details concerning what to do if the LCO statement is not met, consistent with the format of the ISTS Bases. Furthermore, the ISTS Bases describes that the Required Actions restricts the local LHR to a safe level, "allowing movement through the specified applicability conditions in the exception to Specification 3.0.3."
ISTS LCO 3.0.3 provides action to take if no actions are provided in the individual Specifications. Thus, the ACTIONS provided in ISTS 3.2.4 are not an "exception to Specification 3.0.3." Therefore, this paragraph has been deleted.
- 4. Changes are made to reflect the Specification.
- 5. Changes are made to reflect changes made to the Specification.
- 6. The brackets have been removed and the proper plant specific information/value has been provided.
- 7. The ISTS LCO 3.2.4 Bases includes a discussion of "Actual Alarm Setpoints" for QPT. This discussion is not included in the ITS LCO 3.2.4 Bases. The "Actual Alarm Setpoints" are not needed to satisfy the requirements of the LCO and therefore a discussion of the "Actual Alarm Setpoints" is not needed in the LCO Bases.
- 8. Changes are made to be consistent with other places in the Bases (i.e., LCO 3.2.5 Bases Background).
- 9. Change made to be consistent with the Bases of LCO 3.2.4 Required Action A.1.2.2.
- 10. Changes made to be consistent with other places in the Bases.
Davis-Besse Page 1 of 1 Attachment 1, Volume 7, Rev. 0, Page 104 of 132
Attachment 1, Volume 7, Rev. 0, Page 105 of 132 Specific No Significant Hazards Considerations (NSHCs)
Attachment 1, Volume 7, Rev. 0, Page 105 of 132
Attachment 1, Volume 7, Rev. 0, Page 106 of 132 DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATIONS ITS 3.2.4, QUADRANT POWER TILT (QPT)
There are no specific NSHC discussions for this Specification.
Davis-Besse Page 1 of 1 Attachment 1, Volume 7, Rev. 0, Page 106 of 132
, Volume 7, Rev. 0, Page 107 of 132 ATTACHMENT 5 ITS 3.2.5, POWER PEAKING FACTORS , Volume 7, Rev. 0, Page 107 of 132
, Volume 7, Rev. 0, Page 108 of 132 Current Technical Specification (CTS) Markup and Discussion of Changes (DOCs) , Volume 7, Rev. 0, Page 108 of 132
Attachment 1, Volume 7, Rev. 0, Page 109 of 132 ITS 3.2.5 ITS POWER DISTRIBUTION LIMITS NUCLEAR HEAT FLUX HOT CHANNEL FACTOR - F.
LIMITING CONDITION FOR OPFRATTON F shall be within the limits specified in the CORE OPERATING LIMITS I LCO 3.2.5 3.2.2 Fo shall be within the limits specified in the CORE OPERATING LIMITS 3RPORT.
APPLICABILITY: MODE 1 - with THERMAL POWER> 20% RTP L ACTION:
witn rF exceeding itS 1imit:
within ACTION A a. Reduce THERMAL POWER at least 1% for each 1%F exceeds the limit 15 minutes and similarly reduce the high flux trip setpoint and flux-&
flux-flow trip setpoint within - ours. 10 ACTION A b. Demonstrate through incore mapping that Fa is within its limit within 24 2 L0 hours after exceedinq the limit or -re-duce THERMAL POWER to less than 9-of
- ACTION C RATED THERMAL POWER within the next 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />.
m
- c. Identify and correct the c~use of the out of limit londition prior to incre'sing THERMAL POWER ab ve the reduced limit req. ired by a or b, above; subsequent POWER OPEPATION may proceed provlde that F, is demonst ated through incore )apping to be within its imit at a nominal 50% of R[QUIREMENTS TED THERMAL POWER prior to exceeding this THE.WL POWER, at a nominal 5% of RATED THERMAL 1OWER prior to exceeding t is THERMAL POWEI and withi 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after atta'ning 95% or greater RATEL THERMAL POWER.
SURVEILLANCE SURVEILLANCE REQUIREMENTS SR 3.2.5.1 by using the incore 4.2.2.1. F0 shall be determined to be within its limit AdpoodNoetSR3.2.5.1iL0 detectorsto obtain a power distribution map:
Amendment No. dg,18g DAVIS-BESSE, UNIT 1 3/4 2-5 Page 1 of 4 Attachment 1, Volume 7, Rev. 0, Page 109 of 132
Attachment 1, Volume 7, Rev. 0, Page 110 of 132 ITS 3.2.5 ITS Q POWER DISTRIBUTION LIMITS SURVEILLANCE REQUIREMENTS (Continued)
SR 3.2.5.1 a. Prior to initial ~peration above 75 perceit of RATED THERMAL a.\ Prior to initial 4~eration above 75 perce'\t of RATED THERMAL As specified by POWER after each f'7elloading, and the appi*cable LCO(s)n L004
- b. t least once per 31 Effective Full Power Da s.
- c. Tie provisions of Spe.\ification 4.0.4 are not applicable.
I 4.2.2.2 'he measured F of 2.2.1 above, shall be\.ncreased by l.4%
2 LAO01 to account\for manufactgring tlerances and further Ireased by 7.5%
lto account or measurement unce. tainty.
to account for measurement iý DAVIS-BESSE, UNIT 1 3/4 2-6 Page 2 of 4 Attachment 1, Volume 7, Rev. 0, Page 110 of 132
Attachment 1, Volume 7, Rev. 0, Page 111 of 132 ITS 3.2.5 ITS 0 POWER DISTRIBUTION LIMITS N~iCAir CUTAo le Cruio n *JPT* *N I !_i DL6 l~ lmI1FcL rMUIUVK - r.
LIMITING CONDITION FOR OPERATION LCO 3.2.5 3.2.3 FM shall be within the limits specified in the CORE OPERATING LI LIVITS REPORT.
APPLICABILITY: MODE 1. with THERMAL POWER > 20% RTP ACTION:
With Fm,, exceeding its limit: _--RH(%) RTP ACTION BI a. Reduce THERMAL POWER at least I for each 1% that F. exceeds the limit within 15 minutes and similarly reduce the Higg Flux Trip 10 L02 Setpoint and Flux - AFlux - Flow Trip Setpoint within ours.
ACTION B b. Demonstrate through in-core mapping that FNAHis within its limit within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after exceeding the limit or--educe THERMAL POWER to ACTION C less than of RATED THERMAL POWER within the next 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. 20 L01 C.
Iaeentiry anr correct tile cause of the out of limit condition prior To increasing THERMAL P9WER above the reduced limi'f required by a or b above; subsequent POIR OPERATION may proceed pr'vided that FN is demonstrated
.... through sn-core mapping to be withfil its limit at a norinal 50% of RATED THERIAL POWER prior to exceeding this THERMAL POWER, at a nominal 75% of\RATED THERMAL POWER prior to exceeding this THERMAL POWER and witfin 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after attainint 95% or grea \er RATED THERMAL POWER\
DAVIS-BESSE, UNIT 1 314 2-7 Amendment No.189 Page 3 of 4 Attachment 1, Volume 7, Rev. 0, Page 111 of 132
Attachment 1, Volume 7, Rev. 0, Page 112 of 132 ITS 3.2.5 ITS POVER DISTRIBUTION LIITS 1*T 1 .. ýq wwftql*L*
auflvLJ..JdUý- -lUJfl41S Add proposed Note to SR 3.2.5.1 SR 3.2.5.1 4.2.3.1 F shall be determined to be vithin its mit by using the incore As specified by the applicable LCO(s) detectors to obtain a power distribution map:
- a. Pr\or to operation above 75 percent of RATED TIEI POVER after each fue\ loading. and L04
- b. At least once per 31 Effec ive Full Poyer Days.
2 Th. \vienn. Of SnecifiraVion 4.0.4 are not aoolicable.
LAO 1 4.2.3.2
- emeasured AS of 4.\.3.1 above, shall be inclased by 5Z for measurement zk1certainty.
DAVIS-BESSE, EIMT 1 3/4 2-8 Amendment No. 135 Page 4 of 4 Attachment 1, Volume 7, Rev. 0, Page 112 of 132
Attachment 1, Volume 7, Rev. 0, Page 113 of 132 DISCUSSION OF CHANGES ITS 3.2.5, POWER PEAKING FACTORS ADMINISTRATIVE CHANGES A01 In the conversion of the Davis-Besse 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-1430, Rev. 3.1, "Standard Technical Specifications-Babcock and Wilcox 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 3.2.3 Action a requires a reduction of THERMAL POWER at least 1% for each 1% FAH exceeds the limit and a similar reduction in the High Flux and Flux-AFlux-Flow Trip Setpoints. ITS 3.2.5 Required Actions B.1 and B.2 require a reduction of THERMAL POWER and a reduction of the High Flux and Flux-AFlux-Flow Trip Setpoints of> RH (%) RTP for each 1% that F. H exceeds the limit. This changes the CTS by requiring THERMAL POWER and the High Flux and Flux-AFlux-Flow Trip Setpoints be reduced by RH (%) RTP for each 1% that H exceeds the limit instead of by 1% for each 1% that FA H exceeds the limit.
The purpose of CTS 3.2.3 Action a is to reduce the maximum linear heat rate in the core so that protection from departure from nucleate boiling (DNB) during a limiting loss of flow transient is maintained. The proposed RH value will be specified in the COLR, and is currently 3.3%. Thus, the proposed value of THERMAL POWER and Trip Setpoint reduction is greater than the current value provided in CTS 3.2.3 Action a. The proposed value (RH) is based on an analysis of the DNB ratio during the limiting loss of forced reactor coolant flow transient from various initial THERMAL POWER levels. Therefore, the change is considered acceptable. This change is designated as more restrictive because a greater THERMAL POWER and Trip Setpoint reduction is required in the ITS than is required in the CTS.
RELOCATED SPECIFICATIONS None REMOVED DETAIL CHANGES LA01 (Type 3 - Removal of ProceduralDetails for Meeting TS Requirements or Reporting Requirements) CTS 4.2.2.2 requires that the measured FQ of CTS 4.2.2.1 to be increased by 1.4% to account for manufacturing tolerances and further increased by 7.5% to account for measurement uncertainty.
CTS 4.2.3.2 requires that the measured F. H of CTS 4.2.3.1 to be increased by 5% for measurement uncertainty. ITS SR 3.2.5.1 does not require these additional factors to be incorporated. This changes the CTS by relocating the Davis-Besse Page 1 of 5 Attachment 1, Volume 7, Rev. 0, Page 113 of 132
Attachment 1, Volume 7, Rev. 0, Page 114 of 132 DISCUSSION OF CHANGES ITS 3.2.5, POWER PEAKING FACTORS procedural detail to include manufacturing tolerances and measurement uncertainty, as appropriate, in the measurement of FQ and FA H to the Bases.
The relocation of the specific values of the manufacturing tolerances and measurement uncertainties corrections are justified in Discussion of Change LA02.
The purpose of CTS 4.2.2.2 and CTS 4.2.3.2 is to ensure that values of FQ and FAH determined through incore mapping conservatively include allowances for manufacturing tolerances and measurement uncertainty, as appropriate. The removal of these details for performing Surveillance Requirements from the Technical Specifications 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 requirements to perform appropriate verifications of F0 and F. H. 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 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 procedural details for meeting Technical Specifications requirements are being removed from the Technical Specifications.
LA02 (Type 5 - Removal of Cycle-Specific ParameterLimits from the Technical Specifications to the Core OperatingLimits Report) CTS 4.2.2.2 requires that the measured FQ of CTS 4.2.2.1 to be increased by 1.4% to account for manufacturing tolerances and further increased by 7.5% to account for measurement uncertainty. CTS 4.2.3.2 requires that the measured F. H of CTS 4.2.3.1 to be increased by 5% for measurement uncertainty. ITS SR 3.2.5.1 does not require these additional factors to be incorporated. This changes the CTS by relocating the specific values of the manufacturing tolerances and measurement uncertainties corrections, which must be confirmed on a cycle-specific basis, to the COLR. The relocation of the procedural details to make the corrections to the measured F0 and F.'H is justified in Discussion of Change LA01.
The removal of these cycle-specific parameter limits from the Technical Specifications to the COLR is acceptable because the cycle-specific limits are developed or utilized under NRC-approved methodologies which will ensure that the Safety Limits are met. The NRC documented in Generic Letter 88-16, "Removal of Cycle-Specific Parameter Limits From Technical Specifications,"
that 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 verify that the absolute position indicator channels and the relative position indicator channels agree within the limit. The methodologies used to develop the parameters in the COLR have obtained prior approval by the NRC in accordance with Generic Letter 88-16. Also, this change is acceptable because the removed information will be adequately controlled in the COLR under the requirements provided in ITS 5.6.3, "CORE OPERATING LIMITS REPORT." ITS 5.6.3 ensures that the applicable limits (e.g., fuel thermal Davis-Besse Page 2 of 5 Attachment 1, Volume 7, Rev. 0, Page 114 of 132
Attachment 1, Volume 7, Rev. 0, Page 115 of 132 DISCUSSION OF CHANGES ITS 3.2.5, POWER PEAKING FACTORS mechanical limits, core thermal hydraulic limits, Emergency Core Cooling Systems limits, and nuclear limits such as SDM, transient analysis limits, and accident analysis limits) of the safety analyses are met. This change is designated as a less restrictive removal of detail change because information relating to cycle-specific parameter limits is being removed from the Technical Specifications.
LESS RESTRICTIVE CHANGES L01 (Category 2 - Relaxation of Applicability) CTS 3.2.2 and CTS 3.2.3 are both applicable in MODE 1. ITS 3.2.5 is applicable in MODE 1 with THERMAL POWER > 20% RTP. This changes the CTS by reducing the applicable MODES in which the Nuclear Heat Flux Hot Channel Factor (FQ) and Nuclear Enthalpy Rise Hot Channel Factor (F. H) requirements must be met.
The purpose of CTS 3.2.2 and CTS 3.2.3 is to establish limits that constrain the core power distribution within design limits during normal operation and during anticipated operational occurrences such that accident initial condition protection criteria are preserved. This change is acceptable because the requirements continue to ensure that the core power distributions are maintained in the MODES and other specified conditions assumed in the safety analyses and licensing basis. This change revises the Applicabilities of CTS 3.2.2 and CTS 3.2.3 from "MODE 1" to "MODE 1 with THERMAL POWER > 20% RTP."
With THERMAL POWER less than or equal to 20% RTP, the reactor has insufficient stored energy in the fuel or energy being transferred to the coolant to require a limit on the distribution of core power. Along with this change the THERMAL POWER of 5% RTP in the default action (CTS 3.2.2 Action b and CTS 3.2.3 Action c) have been changed to 20% RTP. This change is designated as less restrictive because the LCO requirements are applicable in fewer operating conditions than in the CTS.
L02 (Category 3 - Relaxation of Completion Time) CTS 3.2.2 Action a states the High Flux and Flux-AFlux-Flow trip setpoints must be reduced 1% for each 1%
FQ exceeds its limit within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. The CTS 3.2.3 Action a states the High Flux and Flux-AFlux-Flow trip setpoints must be reduced 1% for each 1% FA H exceeds its limit within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. ITS 3.2.5 Required Actions A.2 and B.2 requires the trip setpoints to be reduced similarly within 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br />. This changes the CTS by extending the Completion Time from 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> to 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br />.
The purpose of CTS 3.2.2 Action a and the CTS 3.2.3 Action a is to reduce the High Flux and Flux-AFlux-Flow trip setpoints when Fa or F. H exceeds its limit in order to maintain both core protection and OPERABILITY margin at the reduced THERMAL POWER. This change is acceptable 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 power reduction required by CTS 3.2.2 Action a, CTS 3.2.3 Action a, and ITS 3.2.5 Required Actions A.1 Davis-Besse Page 3 of 5 Attachment 1, Volume 7, Rev. 0, Page 115 of 132
Attachment 1, Volume 7, Rev. 0, Page 116 of 132 DISCUSSION OF CHANGES ITS 3.2.5, POWER PEAKING FACTORS and B.1, limit the linear heat rate in the core to within an acceptable value. The reduction of the trip setpoints is considered to be a backup that is intended to maintain an OPERABILITY margin comparable to that at RTP, and to provide core protection. The revised Completion Time of 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> is considered reasonable based upon the number of steps required to complete the action and the low probability of an accident occurring during the Completion Time that would require the associated trips to function. This change is designated as less restrictive because additional time is allowed to reduce the trip setpoints than was allowed in the CTS.
L03 (Category 4 - Relaxation of Required Action) CTS 3.2.2 Action c and CTS 3.2.3 Action c require that, in the event FQ and FAH (the power peaking factors),
respectively, are not within limits, the cause of the out of limit condition be identified and corrected prior to increasing THERMAL POWER above the reduced limit required by Actions a or b. In addition, these Actions state that subsequent POWER OPERATION may proceed provided that Fa and FAH, respectively, are demonstrated through in-core mapping to be within their limits at a nominal 50% of RATED THERMAL POWER (RTP) prior to exceeding this THERMAL POWER, at a nominal 75% of RTP prior to exceeding this THERMAL POWER and within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after attaining 95% or greater RTP. ITS 3.2.5 does not contain these actions. This changes the CTS by deleting the requirement to confirm the peaking factors are within limit at 50% RTP, 75% RTP, and 95%
RTP.
The purpose of the CTS 3.2.2 Action c and CTS 3.2.3 Action c is to require confirmation that the core power distributions are within limits during the power increase following an out of limit condition. This change is acceptable because the 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 time to repair inoperable features. The Required Actions are consistent with safe operation under the specified Condition, because only a short time period of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is allowed to operate with the power peaking factors outside of limits. This time period limits the potential for inducing an adverse perturbation in the axial xenon distribution.
Operating the unit in accordance with the requirements of ITS LCO 3.1.4, "CONTROL ROD Group Alignment Limits," LCO 3.2.1, "Regulating Rod Insertion Limits," LCO 3.2.2, "AXIAL POWER SHAPING ROD (APSR) Insertion Limits,"
LCO 3.2.3, "AXIAL POWER IMBALANCE Operating Limits," and LCO 3.2.4, "QUADRANT POWER TILT," provides assurance that the power peaking factors will be maintained within limits. These LCOs provide the Required Actions for correcting the cause of those conditions that could result in power peaking factors exceeding limits. This change is designated as less restrictive because less stringent Required Actions are being applied in the ITS than were applied in the CTS.
L04 (Category 7- Relaxation of Surveillance Frequency - Non-24 Month Type Change) CTS 4.2.2.1 and CTS 4.2.3.1 require, in part, that FQ and FAH, respectively, are determined to be within limits by using the incore detectors to obtain a power distribution map. The Frequencies of the Surveillance Requirements are prior to operation above 75% RTP after each fuel loading, at Davis-Besse Page 4 of 5 Attachment 1, Volume 7, Rev. 0, Page 116 of 132
Attachment 1, Volume 7, Rev. 0, Page 117 of 132 DISCUSSION OF CHANGES ITS 3.2.5, POWER PEAKING FACTORS least once per 31 Effective Full Power Days. The Surveillance Frequency also states that the provisions of Specification 4.0.4 are not applicable. ITS SR 3.2.5.1 requires that F0 and F H,be verified to be within limits by using the Incore Detector System to obtain a power distribution map as specified by the applicable LCO(s). ITS SR 3.2.5.1 is modified by a note that states that the verification is only required to be performed when specified in LCO 3.1.8, "PHYSICS TESTS Exceptions - MODE 1," or when complying with Required Actions of LCO 3.1.4, "CONTROL ROD Group Alignment Limits," LCO 3.2.1, "Regulating Rod Insertion Limits," LCO 3.2.2, "AXIAL POWER SHAPING ROD (APSR) Insertion Limits," LCO 3.2.3, "AXIAL POWER IMBALANCE Operating Limits," and LCO 3.2.4, "QUADRANT POWER TILT." This changes the CTS by deleting the requirement to perform the power peaking factor determinations at the specified Frequencies.
The purpose of CTS 4.2.2.1.b and CTS 4.2.3.1.b is to demonstrate that FQ and FAH are within the limits specified in the respective LCOs. This change is acceptable because operating the unit in accordance with the requirements of ITS LCO 3.1.4, "CONTROL ROD Group Alignment Limits," LCO 3.2.1, "Regulating Rod Insertion Limits," LCO 3.2.2, "AXIAL POWER SHAPING ROD (APSR) Insertion Limits," LCO 3.2.3, "AXIAL POWER IMBALANCE Operating Limits," and LCO 3.2.4, "QUADRANT POWER TILT," provides assurance that the power peaking factors will be maintained within limits. CTS 4.2.2.1.b and CTS 4.2.3.1 .b provide a confirmation of already known conditions, assuming that the unit is being operated within the requirements of LCO 3.1.4, LCO 3.2.1, LCO 3.2.2, LCO 3.2.3, and LCO 3.2.4. However, when required to be verified because of a failure to meet one or more of the referenced LCOs, the power peaking factors will be verified to ensure the continued compliance with the core power distribution assumptions of the accident analyses. This change is designated as less restrictive because Surveillances will be performed less frequently under the ITS than under the CTS.
Davis-Besse Page 5 of 5 Attachment 1, Volume 7, Rev. 0, Page 117 of 132
Attachment 1, Volume 7, Rev. 0, Page 118 of 132 Improved Standard Technical Specifications (ISTS) Markup and Justification for Deviations (JFDs)
Attachment 1, Volume 7, Rev. 0, Page 118 of 132
Attachment 1, Volume 7, Rev. 0, Page 119 of 132 Power Peaking Factors 3.2.5 CTS 3.2 'POWER DISTRIBUTION LIMITS 3.2.5 Power Peaking ;Factors 3.2.2, 3.2.3 LCO 3.2.5 Fo 2] and FANHshall be within the limits specified in the COL:R. 0 APPLICABILITY: MODE 1 with THERMAL POWER > 20% RTP.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME 3.2.2 Action a, 3.2.2 Action b A. F I) not within limit. A.1 Reduce THERMAL POWER > 1% RTP for 15 minutes 0 each 1% that For]
exceeds limit. 0 AND 10 2 A.2 Reduce jnuclear'e~ g-o-we~r ýhours trip setpoint andrnuc earF 0o overpower based ons___
Reactor' oolant Syst. 'm (RCS) flow and AXIV4L POWER IMBALANP,(E trip
~FIuxIIow 0
setpoint > 1% RTP for each 1% that F0 7 exceeds limit.
0 AND A.3 Restore Fa 2) to within limit.
24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> 0
3.2.3 Action a, B. FN not within limit. B.1 Reduce THERMAL 15 minutes 3.2.3 Action b POWER _>RH(%) RTP (specified in the COLR) for each 1% that F"N exceeds limit.
AND BWOG STS 3.2.5-1 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 119 of 132
Attachment 1, Volume 7, Rev. 0, Page 120 of 132 Power Peaking Factors C3.2.5 WCTS ACTIONS (continued)
CONDITION REQUIRED ACTION COMPLETION TIME B.2 Reduce uce ver ower hours trip setpoint and 3.o.erpowCr nuc-le re Rasei AcinaFnd_
3flow an AXIAL POVC/ER /
SIMBALi CEltrip setpoint I - -F-w
>! RH(%) RTP (specified in the COLR) for each 1% that FNHexceeds limit.
AND B.3 Restore F N to within limit. 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> 3.2.2Action b,C. Required Action and CA1 IBe'I&MODE'-withl 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> 3.2.3 Action b im*t-intarl r..nmnlatin~n TW;=PKAA 1C)XAlPP < 9n~o/,,
SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY 4.2.2.1, SR 3.2.5.1 --------------- NOTE---------------
4.2.3.1 Only required to be performed when specified in LCO 3.1.8, "PHYSICS TESTS Exceptions -
MODE 1," or when complying with Required Actions of LCO 3.1.4, "CONTROL ROD Group Alignment Limits," LCO 3.2.1, "Regulating Rod Insertion Limits," LCO 3.2.2, "AXIAL POWER SHAPING ROD (APSR) Insertion Limits," LCO 3.2.3, "AXIAL POWER IMBALANCE Operating Limits," LCO 3.2.4, "QUADRANT POWER TILT (QPT)."
0 Verify FCV and F. are within limits by using the As specified by 0 Incore Detector System to obtain a power the applicable distribution map. LCO(s)
BWOG STS 3.2.5-2 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 120 of 132
Attachment 1, Volume 7, Rev. 0, Page 121 of 132 JUSTIFICATION FOR DEVIATIONS ITS 3.2.5, POWER PEAKING FACTORS
- 1. Changes are made which reflect the plant specific nomenclature.
- 2. The Completion Times of ITS Required Action A.2 and B.2 have been changed from 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> to 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br />. The proposed Completion Times are consistent with the Completion Times for similar actions in ISTS 3.2.4 Required Actions A.1.2.2 and C.2 and in ISTS 3.2.4 Required Action A.2.3.
- 3. Editorial change made to be consistent with other Specifications (i.e., ITS 3.2.3).
- 4. Typographical/grammatical error corrected.
Davis-Besse Page 1 of 1 Attachment 1, Volume 7, Rev. 0, Page 121 of 132
Attachment 1, Volume 7, Rev. 0, Page 122 of 132 Improved Standard Technical Specifications (ISTS) Bases Markup and Justification for Deviations (JFDs)
Attachment 1, Volume 7, Rev. 0, Page 122 of 132
Attachment 1, Volume 7, Rev. 0, Page 123 of 132 Power Peaking Factors B 3.2.5 B 3.2 POWER DISTRIBUTION LIMITS B 3.2.5 Power Peaking Factors BASES BACKGROUND The purpose of this LCO ;is to establish limits that constrain the core power distribution within design limits during normal operation (Condition 1) and during anticipated operational occurrences (Condition 2) such that accident initial condition protection criteria are preserved. The accident initial condition criteria are preserved by bounding operation at THERMAL POWER within specified acceptable fuel design limits.
FQoT is a specified acceptable fuel design limit that preserves the initial 0
con itions for the Emergency Core Cooling Systems (ECCS) analysis.
FQf*-)is defined as the maximum local fuel rod linear power density 0 divided by the average fuel rod linear power density, assuming nominal fuel pellet and rod dimensions. Because FQ M) is a ratio of local power 0 densities, it is related to the maximum local (pellet) power density in a fuel rod. Operation within the F0 f)- limits given in the COLR prevents power 0 peaking that would exceed the loss of coolant accident (LOCA) linear heat rate (LHR) limits derived from the analysis of the ECCS.
The F'H limit is a specified acceptable fuel design limit that preserves the initial conditions for the limiting loss of flow transient. F' H is defined as the ratio of the integral of linear power along the fuel rod on which the minimum departure from nucleate boiling ratio (DNBR) occurs to the average integrated rod power. Because F. H is a ratio of integrated powers, it is related to the maximum total power produced in a fuel rod.
Operation within the F. H limits given in the COLR prevents departure from nucleate boiling (DNB) during a postulated loss of forced reactor coolant flow accident.
Measurement of the core power peaking factors using the Incore Detector System to obtain a three dimensional power distribution map provides direct confirmation that FOR)] and F,'H are within their limits, and may be used to verify that the power peaking factors remain bounded when one 0 or more normal operating parameters exceed their limits.
BWOG STS B 3.2.5-1 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 123 of 132
Attachment 1, Volume 7, Rev. 0, Page 124 of 132 Power Peaking Factors B 3.2.5 BASES APPLICABLE SAFETY The limits on F0 -1) are determined by the ECCS analysis in order to limit peak cladding temperatures to 22007F-during a LOCA. The maximum 0
ANALYSES acceptable cladding temperature is specified by 10 CFR 50.46 (Ref. 1).
Higher cladding temperatures could cause severe cladding failure by oxidation due to a Zircaloy water reaction. Other criteria must also be met (e.g., maximum cladding oxidation, maximum hydrogen generation, coolable geometry, and long termcooling). However, peak-cladding temperature is usually most limiting.
The limits on F. provide protection from DNB during a limiting loss of flowtransient. Proximity to the DNB condition is expressed by the DNBR, defined as the ratio of the cladding surface heat flux required to cause DNB to the actual cladding surface heat flux. The minimum DNBR value during both normal operation and anticipated transients is limited to the DNBR correlation limit for the particular fuel design in use, and is accepted as an appropriate margin to DNB. The DNBR correlation limit ensures that there is at least 95% probability at the 95% confidence level (the 95/95 DNB criterion) that the hot fuel rod in the core does not experience DNB.
This LCO precludes core power distributions that violate the following fuel design criteria:
- a. During a a exceed 2200°F (Ref. 1)I LOCA, peak cladding temperature must not 03
- b. During a loss of forced reactor coolant flow accident, there must be at least 95% probability at the 95% confidence level (the 95/95 DNB criterion) that the hot fuel rod in the core does not experience a DNB condition.
The reload safety evaluation analysis determines limits on global core parameters that characterize the core power distribution. The primary parameters used to monitor and control the core power distribution are the regulating rod position, the APSR position, the AXIAL POWER IMBALANCE, and the QPT. These parameters are normally used to monitor and control the core power distribution because their measurements are continuously observable. Limits are placed on these parameters to ensure that the core power peaking factors remain BWOG STS B 3.2.5-2 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 124 of 132
Attachment 1, Volume 7, Rev. 0, Page 125 of 132 Power Peaking Factors
-B 3.2.5 BASES APPLICABLE SAFETY'ANALYSES (continued) bounded during operation in MODE 1 with'THERMAL POWER greater than 20% RTP. Nuclear design model calculational uncertainty, manufacturing tolerances (e.g:, the engineering hot channel factor),
effects of fuel densification and rod bow, and modeling simplifications (such as treatment of the spacer grid effects) are accommodated through use of peaking augmentation factors in the reload safety evaluation analysis.
FQ0 -) and F'AH satisfy Criterion 2 of 10 CFR 50.36(c)(2)(ii).
LCO This LCO for the power peaking factors FQr1- and F. H ensures that the core operates within the bounds assumed for the ECCS and thermal hydraulic analyses. Verification that Fof-and F. Hare within the limits of this LCO as specified in the COLR allows continued operation at THERMAL POWER when the Required Actions of LCO 3.1.4, "CONTROL ROD Group Alignment Limits," LCO 3.2.1, "Regulating Rod Insertion Limits," LCO 3.2.2, "AXIAL POWER SHAPING ROD Insertion Limits," LCO 3.2.3, "AXIAL POWER IMBALANCE Operating Limits," and LCO 3.2.4, "QUADRANT POWER TILT," are entered. Conservative THERMAL POWER reductions are required if the limits on FQ 0 -M and F, H are exceeded. Verification that FQ]and F*H are within limits is alsoA required during MODE 1 PHYSICS TESTS per LCO 3.1.8, "PHYSICS TESTS Exceptions - MODE 1."
Measurement uncertainties are applied when For)and F* H areIs determined using the Incore Detector System. The measurement uncertainties applied to the measured values of Fo p)and F' H account for uncertainties in observability and instrument string signal processing.
APPLICABILITY In MODE 1 with THERMAL POWER greater than 20% RTP, the limits on FQ0 ]and F"H must be maintained in order to prevent the core power distribution from exceeding the limits assumed in the analyses of the LOCA and loss of flow accidents. In MODE 1 with THERMAL POWER less than or equal to 20% RTP and in MODES 2, 3, 4, 5, and 6, this LCO is not applicable because the reactor has insufficient stored energy in the fuel or energy being transferred to the coolant to require a limit on the distribution of core power.
BWOG STS B 3.2.5-3 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 125 of 132
Attachment 1, Volume 7, Rev. 0, Page 126 of 132 Power Peaking Factors B 3.2.5 BASES APPLICABILITY (continued)
The minimum THERMAL POWER level of 20% RTP was chosen based on the ability of the Incore Detector System to satisfactorily obtain meaningful power distribution data.
ACTIONS The operator must take care in interpreting the relationship of the power peaking factors FQ 0 ) and F. H to their limits. Limit values of F f]and Q FAH in the COLR may be expressed in either LHR or in peaking units.
Because Fc])and F'H are power peaking factors, constant LHR is maintained as THERMAL POWER is reduced, thereby allowing power
- peaking to be increased in inverse proportion to THERMAL POWER.
Therefore, the FQ M) and F1 H limits increase as THERMAL POWER decreases (assuming Fo Wand F', are expressed in peaking units) so that a constant LHR limit is maintained.
A.1 When FQ,r]is determined not to be within its specified limit as C) determined by a three dimensional power distribution map, a THERMAL POWER reduction is taken to reduce the maximum LHR in the core.
Design calculations have verified that a conservative THERMAL POWER reduction is 1% RTP or more for each 1% by which FQ0 exceeds its limit ei []) The Completion Time of 15 minutes provides an acceptable 0 2) time to reduce power in an orderly manner and without allowing the plant to remain in an unacceptable condition for an extended period of time.
A.2 Power operation is allowed to continue by Required Action A.1 if THERMAL POWER is reduced by 1% RTP or more from the F ALLOWABLE THERMAL POWER for each 1% by which F0 -)exceeds its limit. The same re u ion irnuclear erpower trip setpoint and nuclear overpow/er based onhe Reator Coolt System (RCS) flow a 0 cthe AXIAL POVER IMBAae oNCEh rip setpoint is required for each 1% by Fiux-ýFiux-Flow which FQ, is in excess of its limit. These reductions maintain both core (D protection and OPERABILITY margin at the reduced THERMAL POWER.
The required Completion Time of*]hours is reasonable based on the low (C probability of an accident occurring in this short time period and the number of steps required to complete the Required Action.
BWOG STS B 3.2.5-4 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 126 of 132
Attachment 1, Volume 7, Rev. 0, Page 127 of 132 Power Peaking Factors B 3.2.5 BASES ACTIONS (continued)
A.3 Continued operation with FQ n) exceeding its limit is not permitted, Q because the initial conditions assumed in the accident analyses are no longer valid. The required Completion Time of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to restore F 0 I) i within its limits at the reduced THERMAL POWER level is reasonable based on the low probability of a limiting event occurring simultaneously with FQR) exceeding its limit. In addition, it precludes long term depletion (2 with.local LHRs higher than the limiting values, and limits the potential for inducing an adverse perturbation in the axial xenon distribution.
B.1 When F' H is determined not to be within its acceptable limit as determined by a three dimensional power distribution map, a THERMAL POWER reduction is taken to reduce the maximum LHR in the core. The parameter RH by which THERMAL POWER is decreased per 1%
increase in F* H above the limit has been verified to be conservative by design calculations, and is defined in the COLR. The parameter RH is the inverse of the increase in F',H allowed as THERMAL POWER decreases by 1% RTP, and is based on an analysis of the DNBR during the limiting loss of forced reactor coolant flow transient from various initial THERMAL POWER levels. The required Completion Time of 15 minutes is reasonable for the operator to take the actions necessary to reduce the unit power.
B.2 Flux-AFhux-Flow 1When a decrease in THERMAL POWER is required because F', has exceeded its limit, Required Action B.2 requires reduction of the *gh trip setpo int andth nularoeroe on_ RCS fw/ndAXAL rsedu POWER IMBALANCEtripsetpoint. The amount of reduction of these trip setpoints is governed by the same factor (RH(%) for each 1% that Ft H exceeds its limit) that determines the THERMAL POWER reduction. This process maintains core protection by providing margin to the trip setpoints at the reduced THERMAL POWER similar to that at RTP. The parameter RH is specified in the COLR. The required Completion Time of hours is reasonable based on the low probability of an accident occurring in this 10 2 short time period and the number of steps required to complete this Action.
BWVOG STS B 3.2.5-5 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 127 of 132
Attachment 1, Volume 7, Rev. 0, Page 128 of 132 Power Peaking Factors B 3.2.5 BASES ACTIONS (continued)
B.3 Continued operation with F, H exceeding its limit is not permitted, because the initial conditions assumed in the accident analyses are no longer valid. The required Completion Time of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to restore F* H within its limit at the reduced THERMAL POWER level is reasonable based on the low probability of a limiting event occurring simultaneously with FH exceeding its limit. In addition, this Completion Time precludes long term depletion with an unacceptably high local power and limits the potential for inducing an adverse perturbation in the radial xenon distribution.
C.1 If a THERMAL POWER reduction is not sufficient to restore FQ ')]or F. H Q within its limit (i.e., the Required Actions and associated Completion Times for Condition A or B are not met), then THERMAL POWER operation should be significantly reduced. The reactor is placed in MODE 1 with THERMAL POWER less than or equal to 20% RTP in which this LCO does not apply. The required Completion Time of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is a reasonable amount of time for the operator to reduce THERMAL POWER in an orderly manner and without challenging plant systems.
SURVEILLANCE SR 3.2.5.1 REQUIREMENTS Core monitoring is performed using the Incore Detector System to obtain a three dimensional power distribution map. Maximum values of FOR)]
and F, H obtained from this map may then be compared with the Fo and limits in the COLR to verify that the limits have not been exceeded.
Measurement of the core power peaking factors in this manner may be used to verify that the measured values of Fo, ) and FN H remain within their specified limits when one or more of the limits specified by LCO 3.1.4, LCO 3.2.1, LCO 3.2.2, LCO 3.2.3, or LCO 3.2.4 is exceeded, or when LCO 3.1.8 is applicable. If FQ2) and F, H remain within their limits when one or more of these parameters exceed their limits, operation at THERMAL POWER may continue because the true initial conditions (the power peaking factors) remain within their specified limits.
BWOG STS B 3.2.5-6 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 128 of 132
Attachment 1, Volume 7, Rev. 0, Page 129 of 132 Power Peaking Factors B 3.2.5 BASES SURVEILLANCE REQUIREMENTS (continued)
Because the limits on FQo3and F',' are preserved when the parameters specified by LCO 3.1.4, LCO 3.2.1, LCO 3.2.2, LCO 3.2.3, and LCO 3.2.4 0
are within their limits, a Note is provided in the SR to indicate that monitoring of the power peaking factors is required only when complying with the Required Actions of these LCOs and when LCO 3.1.8 is applicable.
Frequencies for monitoring of the power peaking factors are specified in the Action statements of the individual LCOs. These Frequencies are reasonable based on the low probability of a limiting event occurring simultaneously with either FQ-or F', exceeding its limit, and they provide sufficient time for the operator to obtain a power distribution map 0
from the Incore Detector System. Indefinite THERMAL POWER operation in a Required Action of LCO 3.1.4, LCO 3.2.1, LCO 3.2.2, LCO 3.2.3, or LCO 3.2.4 is not permitted, in order to limit the potential for exceeding both the power peaking factors assumed in the accident analyses due to operation with unanalyzed core power distributions and spatial xenon distributions beyond their analyzed ranges. 0 REFERENCES 1. 10CFR50.46.
The measured values are required to be adjusted to account for manufacturing tolerances and measurement]
uncertainties before being compared to the acceptance criteria specified in the COLR. These adjustments are included in the COLR.
BWOG STS B 3.2.5-7 Rev. 3.0, 03/31/04 Attachment 1, Volume 7, Rev. 0, Page 129 of 132
Attachment 1, Volume 7, Rev. 0, Page 130 of 132 JUSTIFICATION FOR DEVIATIONS ITS 3.2.5 BASES, POWER PEAKING FACTORS
- 1. These punctuation corrections have been made consistent with the Writer's Guide for the Improved Standard Technical Specifications, TSTF-GG-05-01, Section 5.1.3.
- 2. Changes are made to reflect changes made to 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. This parenthetical Reference has been deleted. The ISTS Bases does not provide a specific reference in the References Section, and other similar Actions Bases (A.2, B.1, and B.2) do not specify a Reference.
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Attachment 1, Volume 7, Rev. 0, Page 131 of 132 Specific No Significant Hazards Considerations (NSHCs)
Attachment 1, Volume 7, Rev. 0, Page 131 of 132
Attachment 1, Volume 7, Rev. 0, Page 132 of 132 DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATIONS ITS 3.2.5, POWER PEAKING FACTORS There are no specific NSHC discussions for this Specification.
Davis-Besse Page 1 of 1 Attachment 1, Volume 7, Rev. 0, Page 132 of 132