ML20154M455
| ML20154M455 | |
| Person / Time | |
|---|---|
| Site: | LaSalle  |
| Issue date: | 10/16/1998 |
| From: | Dacimo F COMMONWEALTH EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML20138L307 | List: |
| References | |
| NUDOCS 9810200297 | |
| Download: ML20154M455 (17) | |
Text
Commonw ealth 1:dison Company Imalle Generating Station 2Mt North 21st Road
.\larseilles,1L 6U ii AT?$7 Tel H15-3574761 4
October 16,1998 United States Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555
Subject:
Application for Amendment to Appendix A, Technical Specifications to Facility Operating Licenses LaSalle County Nuclear Power Station, Units 1 and 2 4
Facility Operating License NPF-11 and NPF-18 NRC Docket Nos. 50-373 and 50-374 Change to Setpoint for Psy...
Pursuant to 10 CFR 50.90, Commonwealth Edison (Comed) proposes to amend Appendix A, Technical Specifications, of Facility Operating Licenses NPF-11 and NPF-18, LaSalle County Station Units 1 and 2. The proposed changes to the Technical Specifications (PS) include lowering the power level (Psy...) below which the turbine control valve (TCV) and turbine stop valve (FSV) closure scram signals and the end-of-cycle recirculation pump trip (EOC-RPT) signals are not in effect.
The proposed setpoint changes are supported by an analysis performed by General Electric.
This analysis determined that revisions were necessary to the power dependent core thermal limits. The analysis, performed for Unit 1 Cycle 8,is representative oflimits that will be determined each cycle as part of the normal reload licensing process. Unit 1 will implement the
- revised thermal limits through a revised Core Operating Limits Report (COLR) in the middle of Cycle 8 operation, upca approval and implementation of this amendment request. For Unit 2, thermal limits will be determined by Siemens Power Corporation and will be implemented under 10CFR50.59 as part of the normal reload licensing process. Prior to Unit 2 Cycle 8 startup, a revised COLR that includes these limits will be implemented.
, IN dReduction of the bypass setpoint for the TSV and TCV closure scram signals and the EOC-RPT signals (Psyo.) results in simplified reload transient analyses and lower required thermal limits due to the decreased severity oflow power transients. The analyses currently require more restrictive thermal limits below 30% power because the anticipatory TCV and TSV closure l
scrams do not occur and cannot be credited in the analyses. Therefore, by lowering Psy...,
operating margin is gained. This results in increased operating flexibility at low power levels. By lowering Psyu, to 25% power, the complexity of reload analyses is reduced, resulting in future \ i cost savings. The cost savings from the simplification of the transient analyses amounts t O
$130,000 per cycle per unit, or over $1.8 million over the life of the two units.
(b 2.
SR Lli Eh [
\ .\ pf 9810200297 981016 I PDR ADOCK 050003 R *4 P PDR g l
October 15,1998 Page 2 U.S. Nuclear Regulatory Commission l
f The proposed amendment request is subdivided as follows:
- 1. Attachment A provides a description and safety analysis of the proposed changes in this amendment.
- j. 2. Attachment B includes a summary of the proposed changes and the
- marked-up Technical Specifications pages for LaSalle Units 1 and 2 with I the requested changes indicated.
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- 3. Attachment C describes Comed's evaluation performed in accordance with {
10CFR50.92(c), which confirms that no Significant Hazards Consideration l is involved.
- 4. Attachment D provides an Environmental Assessment Applicability i Review per 10CFR51.21.
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- 5. Attachment E is the General Electric ARTS Improvement Program Analysis for LaSalle County Nuclear Station Units 1 and 2 : Removal of Direct Scram Bypassed Limits.
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Improvement Program Analysis for LaSalle County Nuclear Station Units 1 l and 2 : Removal of Direct Scram Bypassed Limits
- 7. Attachment G contains non-proprietary information that was extracted from the GE Analysis presented in Attachment E.
This request for a Technical Specification Amendment has been reviewed and approved by On-Site and Off-Site Review in accordance with Comed procedures.
The attached General Electric ARTS Improvement Program Analysis Report contains information proprietary to General Electric Company. In accordance with the requirements of 10CFR2.790(b), an affidavit for this report is enclosed as Attachment F to support the withholding of this report from public disclosure. In addition, non-proprietary information that was extracted from the raport is included with this submittal (Attachment G).
, Comed requests that NRC review of this proposed amendment be completed by l March 18,1999, which is prior to the current schedule for Unit 2 Cycle 8 startup. This schedule will allow the instrument calibrations, procedure changes, and Core Operating Limits Report updates to be performed with assurance that this request is acceptable.
Implementation would be prior to startup of L2C8 for Unit 2 and within 90 days of approval of this request for Unit 1. The change to Unit 1 will therefore be performed on-line and will require a mid-cycle COLR update, which will be provided upon implementation per Technical Specification 6.6.A.6.d.
Comed is notifying the state ofIllinois of this application for amendment by transmitting a
! copy of this letter and its attachments to the designated State Official.
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October 15,1998 Page 3 U.S. Nuclear Regulatory Commission I affirm that the content of this transmittal is true and correct to the best ofmy knowledge, information and belief.
If there are any q.restions or conunents concerning this letter, please refer them to Perry L Bames, Regulatory Assurance Manager, at (815) 357-6761, extension 2383.
U Fred R. Dacimo Site Vice President LaSalle County Station Subscribed and sworn to before me, a Notary Public in and
/ +4 for the State ofIllinoi*, this /Is - day of 0Facu
[
(3 du D /99[ ,
DEBRAJ.FEENEY NOTAR/ PU8LIC, STATE OFILLIN018 MY COMMISSION EXPIRES 1012000 OtlvtA 0 asmo11)
Nota'ry Public
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Attachments cc: J. L Caldwell, Acting NRC Region III Administrator D. M. Skay, NRC Project Manger - NRR - LaSalle M. P. Huber, NRC Senior Resident . inspector - LaSalle Office of Nuclear Facility Safety, IDNS
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l ATTACHMENT F i 1
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WITHHOLDING AFFADAVIT ,
FOR GENERAL ELECTRIC REPORT
_. ._ ._ _~ . _ - ~ _ _ _ _ __ _ __ . __
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General Electric Company l
! I,' David J. Robare, being duly sworn, depose and state as follows:
i (1) I am a Technical Account Manager, Technical Services Projects, General Electric Company ("GE") and have been delegated the function of reviewing the information described in paragraph (2) which is sought to be withheld, and have been authorized to apply for its withholding.
(2) The information sought to be withheld is contained in the GE proprietary report GE-NEDC-31531P, ARTSImprovement Program Analysisfor LaSalle County Nuclear Station, Units 1 and 2, Removal of Direct Scram Bypassed Limits, Supplement 1, Class III (GE Company Proprietary Information), dated September 1998. The proprietary information is delineated by bars marked in the margin adjacent to the l specific material.
L (3) In making this application for withholding of proprietary infornation of which it is the owner, GE relies upon the exemption from disclosure set forth in the Freedom of Information Act ("FOIA"), 5 USC Sec. 552(b)(4), and the Trade Secrets Act,18 USC Sec.1905, and NRC regulations 10 CFR 9.17(a)(4), 2.790(a)(4), and 2.790(d)(1) for " trade secrets and commercial or financial information obtained from
- a person and privileged or confidential" (Exemption 4). The material for which exemption from disclosure is here sought is all " confidential commercial information",
and some portions also qualify under the narrower definition of" trade secret", within the meanings assigned to those terms for purposes of FOIA Exemption 4 in,
- l. respectively, Critical Mass Enerav Project v. Nuclear Regulatory Commission.
l 975F2d871 (DC Cir.1992), and PubHc Citizen Health Research Group v. FDA.
j 704F2dl280 (DC Cir.1983).
(4) Some examples of categories of imormation which fit into the definition of proprietary information are:
- a. Information that discloses a process, method, or apparatus, including supporting data and analyses, where prevention ofits use by General Electric's competitors without license from General Electric constitutes a competitive economic advantage over other companies;
- b. 'Information which, if used by a competitor, would reduce his expenditure of i
resources or improve his competitive position in the design, manufacture,
- shipment, installation, assurance of quality, or licensing of a similar product; l
12/13/93RTl!
Affidavit Page 1 l
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Information which reveals cost or price information, production capacities, budget levels, or commercial strat gies of General Electric, its customers, or its suppliers;
- d. Information which reveals aspects of past, present, or future General Electric l
customer-funded development plans and programs, of potential commercial value to General Electric; ei Information which discloses patentable subject matter for which it may be desirable to obtain patent protection.
The information sought to be withheld is considered to be proprietary for the reasons 3
set forth in both paragraphs (4)a. and (4)b., above.
(5) The inforn.ation sought to be withheld is being submitted to NRC in confidence. The information is of a sort customarily held in confidence by GE, and is in fact so held.
The information sought to be withheld has, to the best of my knowledge and belief, consistently been held in confidence by GE, no public disclosure has been made, and it is not available in public sources. All disclosures to third parties including any ,
required transmittals to NRC, have been made, or must be made, pursuant to l regulatory provisions or proprietary agreements which provide for maintenance of l the information in confidence. Its initial designation as proprietary information, and I the subsequent steps taken to prevent its unauthorized disclosure, are as set forth in paragraphs (6) and (7) following. 1 (6) Initial approval of proprietary treatment of a document is made by the manager of the originating component, the person most likely to be acquainted with the value and sensitivity of the information in relation to industry knowledge. Access to such documents within GE is limited on a "need to know" basis.
(7) The procedure for approval of external release of such a document typically requires review by the staff manager, project manaEer, principal scientist or other equivalent authority, by the manager of the cognizant marketing function (or his delegate), and by the Legal Operation, for technical content, competitive effect, and determination of the accuracy of the proprietary designation. Disclosures outside GE are limited to regulatory bodies, customers, and potential customers, and their agents, suppliers, and licensees, and others with a legitimate need for the information, and then only in accordance with appropriate reguMory provisions or proprietary agreements.
(8) The information identified in paragraph (2), above, is classified as proprietary because it contains detailed results of analytical models, methods and processes, including computer codes, which GE has developed, obtained NRC approval of, and applied to perform evaluations of the loss-of-coolant accidents and transients for the BWR.
4 12/13/93RTH Asidavit Page 2
The development and approval of the BWR loss-of-coolant accident and transient analysis computer codes used in this analysis was achieved at a significant cost, on the order of several million dollars, to GE.
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' The development of the evaluation process along with the interpretation and application of the analytical results is derived from the extensive experience database that constitutes a major GE asset.
(9) Public disclosure of the information sought to be withheld is likely to cause substantial harm to GE's competitive position and foreclose or reduce the availability of profit-making opportunities. The information is part of GE's comprehensive BWR safety and technology base, and its commercial value extends beyond the original j
development cost. The value of the technology base goes beyond the extensive l
physical database and analytical methodology and includes development of the
!. expertise to determine and apply the appropriate evaluation process. In addition, the l technology base includes the value derived from providing analyses done with l NRC-approved methods.
The research, development, engineering, analytical and NRC review costs comprise a substantial investment of time and money by GE.
i The precise value of the expertise to devise an evaluation process and apply the correct analytical methodology is difficult to quantify, but it clearly is substantial.
L GE's competitive advantage will be lost ifits competitors are able to use the results of the GE experience to normalize or verify their own process or if they are able to claim an equivalent understanding by demonstrating that they can arrive at the same or similar conclusions.
The value of this information to GE would be lost if the information were disclosed to the public. Making such information available to competitors without their having been required to undertake a similar expenditure of resources would unfairly provide
' competitors with a windfall, and deprive GE of the opportunity to exercise its competitive advantage to seek an adequate return on its large investment in developing these very valuable analytical tools.
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t 1v13/93RTH AHidavit Page 3 l
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i STATE OF CALIFORNIA )
) ss: i l COUNTY OF SANTA CLARA ) l David J. Robare, being duly swom, deposes and says:
- l That he has read the foregoing affidavit and the matters stated therein are true and correct j
to the best of his knowledge, information, and belief.
! Executed at San Jose, California, this 3 day of SEFtM8cR 1998.
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l David J. Robare General Electric Company l l
Subscribed and swom before me this 8 day of [$dIV2/h 1998.
1 A
M/b No"tary Public, State of California
! 4 ANNA HANUN g i Commision # 11s4sy i ' % Public-Coffemia !
i sonfo Clara County r WComm.BehnJun 19,200 l
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't
- 12/13/93RTH Affidavit Page 4 l
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l ATTACHMENT A LASALLE COUNTY STATION i
DESCRIPTION AND SAFETY ANALYSIS OF PROPOSED AMENDMENT TO FACILITY OPERATING LICENSES NPF-11 AND NPF-18 l APPENDIX A, TECHNICAL SPECIFICATIONS l
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ATTACHMENT A DESCRIPTION AND SAFETY ANALYSIS OF THE PROPOSED CHANGES DESCRIPTION OF THE PROPOSED CHANGE This'Technica, Specification Amendment request proposes to amend Appendix A, Technical Specifications, of Facility _ Operating Licenses NPF-11 and NPF-18, Section 3.3.4.2, Tables 3.3.1-1 and 3.3.4.2-1, and Bases Section 3/4.3.4, to revise the Unit 1 and Unit 2 setpoint for the power level below which the Turbine Control Valve (TCV) and Turbine Stop Valve (TSV) closure scram signals and the End of Cycle Recirculation Pump Trip (EOC-RPT) signals are automatically bypassed. The setpoint (P,,,) is based on 30% of Rated Thermal Power, which is measured using first stage turbine pressure and is currently set at 140 psig perTechnical Specifications 3.3.1 and 3.3.4. It is proposed to be decreased to 25% of Rated Thermal Power with the turbine first stage pressure reference deleted from the Technical Specifications. A sentence context error is also corrected, and a requirement is added to periodically verify that TCV and TSV scram trip functions and the EOC-RPT trip functions are not bypassed when > 25% of Rated Thermal Power.
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. DESCRIPTION OF THE CURRENT OPERATING LICENSEITECHNICAL
~ SPECIFICATION REQUIREMENT -
LaSalle Units 1 and 2 Technical Specifications Table 3.3.1-1 describes the !
applicable operational conditions, minimum number of required operable l channels', and appropriate actions for Reactor Protection System Instrumentation. TSV closure and TCV fast closure are both listed as functional units. The values of core thermal power and turbine first stage pressure that make up the bypass setpoint for the TCV.and TSV closure scram signals are provided in Action #6 and in Table Notation 'i'. Those values are currently 30% (rated thermal power) and 140 psig (turbine first stage pressure).
LaSalle Units 1 and 2 Technical Specifications Section 3.3.4.2 and associated Bases Section 3/4.3.4 describe the operability,.setpoint, and response time requirements for EOC-RPT system instrumentation. The Applicability and Action statements provide the core thermal power value below which the EOC-RPT requirements do not apply. That value is currently 30% of rated thermal power. Table _3.3.4.2-1 describes the channel operability requirements of the trip functions associated with the EOC-RPT system.' The trip functions include TSV and TCV closures. Footnote 'b' A-1
provides the values of core thermal power and turbine first stage pressure that constitute the bypass setpoint for both trip functions (30% and 140 psig, respectively).
BASES FOR THE CURRENT OPERATING LICENSE / TECHNICAL SPECIFICATION REQUIREMENT LaSalle Units 1 and 2 each have approximately 30% bypass capability.
Therefore, a scram on TGV or TSV closure signals is not needed until 30%
core thermal power is reached, as adequate steam bypass capacity is available. This bypass capability provides flexibility in that a reactor scram can be avoided if the turbine trips below 30% power. Transient analyses have been performed in the past to support the current P%,,,, setpoint. l These analyses do not credit the TSV and TCV closure scrams and EOC-RPT below Pgg. .. LaSalle utilizes power and flow dependent (ARTS) thermal limits (approved in Reference 1). The power dependent portion of these thermallimits is dependent on the Pg,,,, setpoint. These limits provide assurance that adequate Minimum Critical Power Ratio (MCPR) and fuel thermal-mechanical margin is maintained.
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DESCRIPTION OF THE NEED FOR AMENDING THE TECHNICAL SPECIFICATIONS Reduction of the bypass setpoint for the TSV and TCV closure scram signals i and the EOC-RPT' signals (P%p ..) results in simplified reload transient 2nalyssand lower required thermallimits. The analyses currently require more restrictive thermal limits between 25% and 30% power because the anticipatory.TCV and TSV closure scrams do not occur and cannot be credited in the analyses. Therefore, by lowering P%,,,, to 25%, operating margin is ga ined, resulting in increased operating flexibility at low power levels. Also, by lowering P %,,,, to 25% power, the complexity of reload analysis is reduced, resulting in future cost savings. The cost savings from the simplification of the transient analyses amounts to $130,000 per cycle per !
unit, or over $1.8 million over the life of the two units. l l
DESCRIPTION OF THE AMENDED TECHNICAL SPECIFICATION REQUIREMENT The requested amendment would change the bypass setpoint of the TCV l and TSV closure scram signals and the EOC-RPT signals to > 25% of Rated Thermal Power and delete the reference to turbine first stage pressure.
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l Note (i) is being added to Table 4.3.1.1-1 and note (a) is being added to l Table 4.3.4.2.1-1 to re Wre verification at least once per 18 months that the TSV and TCV closure trip functions are not bypassed at 225% of Rated Thermal Power. The note will include a statement that specification 4.0.2 applies to the 18-month interval.
In addition, a sentence context error is corrected. The current wording of the requirement, in both Table 3.3.1-1 Table note 'i' and Table 3.3.4.2-1 note (b),
states that the function (referring to the TCV and TSV closure scrams and EOC-RPT) shall be automatically bypassed when turbine first stage pressure i is less than or equal to 140 psig, equivalent to thermal power less than 30%
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of rated thermal power. The new requirement would reword this sentence to state that the scram signals shall not be automatically bypassed at 225% of Rated Thermal Power. The pioposed wording corrects the sentence to l properly enforce the basis of the requirement, which ensures that the signals l are not still automatically bypassed when above 25% core thermal power. l The proposed wording is consistent with the wording provided in NUREG-1434, " Standard Technical Specifications, General Electric Plants, BWR/6",
Rev.1. Marked copies of the affected Technical Specifications sections are provided in Attachment B.
BASES FOR THE AMENDED TECHNICAL SPECIFICATION REQUIREMENT Introduction Although LaSalle Units 1 and 2 currently each have approximately 30%
bypass capability, the bypass of the TCV and TSV closure scrams and the EOC-RPT actuation below 30% power is not needed between the 25% and 30% power levels. The bypass is only necessary up to the power level where the turbine is placed on-line, typically at approximately 12% power.
Changing P%,,,, to 25% power could result in more automatic scrams (i.e.,
between 25% and 30% core thermal power in the event of a turbine trip),
however it is not believed that LaSalle would have turbine problems in the range of power between 25% and 30%, and the benefits of reducing Pq ,,,,
outweigh the commercial risks of this change.
Reduction of the bypass setpoint to 25% power results in simplified reload transient analyses and lower required thermallimits. The analyses currently require more restrictive thermal limits between 25% and 30% power because the anticipatory TCV and TSV closure scrams and EOC-RPT do not occur and cannot be credited in the analyses. Therefore, by lowering Pwp ,, to 25%,
4 operating margin is gained between those power levels. This results in increased operating flexibility.
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l l Overview of Supportino Analyses l The proposed setpoint changes are supported by an analysis performed by l General Electric. This analysis determined that revisions to the power dependent core thermal operating limits are necessary. The current ARTS generic power dependent limits for Maximum Average Planar Linear Heat Generation Rate (MAPLHGR) and MCPR are extremely restrictive between
! 25% and 30% power. Upon reaching 30% power, the limits step change to less limiting values, reflecting the improved plant transient response.
Adjustments to the limits, as determined in the GE Pwy,, analysis, are simple linear extensions of the 30% power limits down to 25% power. Transient cases were run at low power and high flow conditions to prove that the l extrapolation is conservative (with respect to the change irt critical power ratio l and to thermal-mechanical criteria). The new limits were determined through use of the NRC-approved ODYN reactor dynamic model and are based on l
the limiting power dependent transients, the Load Rejection Without Bypass (LRNBP) and Feedwater Controller Failure (FWCF) events. These 9 vents exhibit very different responses, depending upon whether power is above or l .
below P wy . The sequence of events for these transients are discussed in the following section, j Transient Analyses Comoarison - Above and Below P %,,
l This section details the sequence of events of the LRNBP and FWCF l transients, both above and below P%, .. The discussions are centered around operation with no Equipment Out of Service (EOOS) penalties applied. Various EOOS combinations are allowed in the LaSalle Core l Operating Limits Reports. These combinations have been analyzed for the l
- revised Pw,,, setpoint, as discussed in the GE analysis, but are not detailed in this section.
L The first transient discussed is the LRNBP transient initiating above P w ,, .
l Upon load rejection above Pw,,,, the TCVs are closed, initiating the TCV l closure scram and recirculation pump runback. The system pressurizes, l causing a change in the core void fraction, resulting in a large neutron flux l change that is dependent on the pressurization and void collapse. The I neutron flux peak increase is usually turned around by the heat addition to
- the moderator and corresponding void increase. However, very soon after
- the peak neutron flux, control rods enter the core due to the direct scram and il the consequences of the event are mitigated. The immediate scram limits the -
neutron flux excursion and limits the peak heat flux increase, and as such directly. influences the thermal limits. The core thermal limits are a strong function of the transient peak heat flux. The recirculation runback also aids in i mitigating the event as core flow is immediately decreased, which decreases the power response.
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The FWCF event above Po ,,, has a very similar sequence of events. The difference for the FWCF is that there is an overcooling phase due to increased feedwater flow. This overcooling phase increases the core inlet subcooling, reduces the core void fraction, and increases the core power. As excess feedwater is added, the reactor water level increases to the Level 8 turbine trip setpoint. Upon turbine trip, the turbine stop valves are closed, initiating the stop valve position scram and recirculation pump runback. The stop valve closure pressurizes the system, and the sequence of events is similar to the load rejection with the stop valve position scram trip mitigating the consequences of the event. For the FWCF, the main steam bypass system is assumed to function to limit the pressurization.
Analyses below P%,,, are much more severe. For these analyses, the direct l scram on TCV or TSV closure and the EOC-RPT actuation do not occur. l Therefore, for a load rejection or turbine trip, a direct scram does not occur. i For a LRNBP, the pressurization results in a large neutron flux change. The initial neutron flux increase is turned around by the heat addition to the moderator, but since a direct scram does not occur, neutron flux will begin to ,
increase once again. Reactor pressure and power will continue to increase l until the high reactor pressure scram setpoint is reached. This scram l eventually mitigates the consequences of this event. However, the scram occurs weH after a large heat flux change. The large change in heat flux requires more restrictive thermal limits to protect the fuel for this event. The results of the analysis require a large step change in thermal limits at the P3,,, power level.
For a FWCF below Pggs., the sequence is similar. When the Level 8 turbine trip setpoint is reached and the TSVs close, there is no direct scram. Reactor pressure and power continue to increase as described above, but at a slower rate because the bypass system is available. The transient is typically mitigated by the high reactor pressure scram. However, as discussed above, the transient is not mitigated until there is a large change in heat flux, resulting in the need for more restrictive thermal limits below w P ,,..
Due to the high thermal margin available at low power levels, thermal limits monitoring is only required at 225% power per LaSalle Technical Specifications. Therefore, transient analyses are only performed at 225%
power. With the Pw,,, setpoint at 25% power, the LRNBP and FWCF transients would behave as described above for the analyses above P wn ..
The transient analysis consequences for analyses between 25% and 30%
power would be much less severe than with the Pwn., setpoint at 30% power.
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l There would not be a need for a large step change in thermal limits at 30%
power and there would be a large increase in thermal margin for plant operations.
l l For Unit 2, additional thermal limits will be determined by Siemens Power Corporation (SPC) and will be implemented under 10CFR50.59 as part of the l normal reload licensing process. Prior to Unit 2 Cycle 8 startup, a revised COLR that includes these limits will be implemented and transmitted per Technical Specification 6.6.A.6.d. The GE analyses are representative of these similar SPC analyses.
Analysis Assumptions and Acolicability in addition to the Pwy,, change, the GE analysis also discusses several other changes (dome pressure vs. power assumptions and APRM flux scram analytical value). These changes have been previously evaluated in accordance with 10CFR50.59 (for thermal operating limits assuming a Pwn,,
of 30%), and are not part of this amendment request. The changes are discussed in the GE analysis because several open analysis issues were resolved for Comed by GE in one document.
The GE analysis was performed with Unit 1 Cycle 8 core characteristics. The resulting thermal limits are representative of limits that will be determined each cycle as part of the normal reload licensing process. Unit 1 will implement the revised thermallimits through a revised Core Operating Limits Report (COLR) in the middle of Cycle 8 operation, upon approval and implementation of this amendment request.
Imoact of Chance On Other Analyses The LRNBP and FWCF events are the only aspects of the LaSalle transient and accident analysis that are impacted by this change. Other events, such as the Loss-of-Coolant Accident, Anticipated Transients Without Scrams, and the ASME Overpressurization Event are only performed at rated plant conditions. Thus, the assumptions remain valid because this change only impacts low power analyses. Similarly, other UFSAR transients either remain non-limiting or are not evaluated for power-dependency, as they are less severe at reduced power conditions.
- Deletion of the Reference to the Eauivalent Turbine First Staae Pressure The Pwg , setpoint is measured in the plant via first stage turbine pressure.
Reference to this pressure and the value is deleted from the Technical l Specification Table 3.3.1-1 Action 6 and Note (i) and Table 3.3.4.2-1 Note (b).
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1 Listing the pressure is unnecessary detail in the Technical Specifications. l Deletion of the pressure is consistent with other LaSalle Technical l Specifications, such as the following Technical Specifications: I
. Surveillance Requirement 4.1.3.2.a: ". . prior to THERMAL POWER exceeding 40% of RATED THERMAL POWER."
e 3.1.4.1 Applicability: ... when THERMAL FOWER is less than or equal to 10% of RATED THERMAL POWER..."
. 3.2.1 Applicability:" .. greater than or equal to 25% of RATED THERMAL POWER".
Technical Specification 3.1.4.1 Low Power Setpoint bypass is automatic like the bypass of the TSV and TCV closure trip functions. The others are administratively controlled only.
In addition, listing only the percent of Rated Thermal Power is consistent with NUREG-1434, " Standard Technical Specifications, General Electric Plants, BWR/6", Rev.1, Surveillance Requirements SR 3.3.1.1.16 and SR 3.3.4.1.5.
Periodic Verification of Bvoass Function A requirement to verify that the TSV Closure and TCV Fast Closure Trip Functions are not bypassed when Thermal Power is 2 25% of Rated Thermal Power at least once per 18 months is proposed to be added to Technical Specification Table 4.3.1.1-1 as Note (i) and to Table 4.3.4.2.1-1 as Note (a).
The proposed requirement will assure the setpoint of the instrumentation -
used to bypass the trips is maintained such that the trips are not bypassed at 2 25% of Rated Thermal Power. The setpoint incorporates adequate margins for the instrument setpoint methodology. Since this proposed periodic verification is a note and not a standard surveillance requirement, the ncte also states that specification 4.0.2 applies to this 18-month interval, which is consistent with instrumentation of similar kind.
This proposed change is consistent with NUREG-1434, " Standard Technical Specifications, General Electric Plants, BWR/6", Rev.1, Surveillance Requirements SR 3.3.1.1.16 and SR 3.3.4.1.5. The proposed Notes are shown as inserts for the associated Technical Specification pages in Attachment B.
Context Error Correction Technical Specification Table 3.3.1-1 Note (i) and Table 3.3.4.2-1 Note (b) are proposed to be reworded to state that the scram sianals shall not be automatically bypassed at areater than or eaual to 25% of Rated Thermal Power (rather than stating that the signals shall be automatically bypassed A-7
below the Pw,,, setpoint). This proposed change corrects the sentence context to properly enforce the basis of the requirement. The change will assure that the TCV and TSV scram and EOC-RPT actuation will be l available above Pg,,, to conform to the transient analysis assumptions. The l new wording ensures that the signals are not still automatically bypassed when above 25% core thermal power. !
Technical Specification Bases Chanaes l
l The Bases for Technical Specification 3/4.3.4 is being updated based on the proposed changes.
SCHEDULE Comed requests that NRC review of this proposed amendment be completed by March 18,1999, which is prior to the current schedule for Unit 2 Cycle 8 startup. This schedule will allow the instrument calibrations, procedure changes, and Core Operating Limits Report updates to be performed with assurance that this request is acceptable. Implementation would be prior to startup of L2C8 for Unit 2 and within 90 days of approval of this request for Unit 1. The change to Unit 1 will therefore be performed on-line and will '
require a mid-cycle COLR update, which will be provided upon implementation per Technical Specification 6.6.A.6.d.
REFERENCE
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- 1. Issuance of Amendment Nos. 88 and 103 for LaSalle County Station Units 1 and 2 (ARTS Thermal Limits Amendments), TAC Nos.
M89631 and M89632, April 13,1995.
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