TXX-9521, Suppl LAR 95-03 Which Revises TS by Removing Several Cycle Specific Parameter Limits & Adding Limits to Colr,Per Discussions W/Nrc

Suppl LAR 95-03 Which Revises TS by Removing Several Cycle Specific Parameter Limits & Adding Limits to Colr,Per Discussions W/Nrc

ML20087L447
Person / Time
Site:	Comanche Peak
Issue date:	08/15/1995
From:	Kelley J, Terry C TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20087L449	List: ML20087L458 TXX-9521, Suppl LAR 95-03 Which Revises TS by Removing Several Cycle Specific Parameter Limits & Adding Limits to Colr,Per Discussions W/Nrc
References
TXX-95213, NUDOCS 9508250247
Download: ML20087L447 (10)

Text

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== Log # TXX 95213 File # 916 (2.1) l--

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Ref. # 10CFR50.90 l 7t# ELECTRIC 10CFR50.36 August 15, 1995 C. lance Terry Groep Ykr Pmidru.Naher U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555

SUBJECT:

COMANCHE PEAK STEAM ELECTP,IC STATION (CPSES)

DOCKET NOS. 50 445 AND 50 446 LICENSE AMENDMENT REQUEST 95 03, SUPPLEMENT ONE CYCLE SPECIFIC PARAMETER LIMITS REACTOR CORE SAFETY LIMITS  !

REF: 1) TV Electric letter logged. TXX 95076 from C. L. Terry to the NRC dated May 12, 1995 Gentlemen:

The proposed changes in this license amendment request (LAR) were originally submitted in LAR 95-03 on May 12,1995 (reference 1). Based on subsequent discussions with the NRC, LAR 93 03 is being divided into four separate LARs for ease in processing by the NRC and to allow review of the four basic changes separately. This supplement to LAR 95 03 retains the changes which move the Reactor. Core . Safety _ Limits figure from the Technical Specifications to the Core Operating Limits Report. (The remaining changes originally in LAR 95 03 are being resubmitted in LARs 95 04, 95 05 and 95 06.) LAR 95 03 is replaced in its entirety by this supplement one. The proposed changes will result in resource savings for TV Electric and the NRC by eliminating license amendment requests now required to change the values of these parameters. The proposed changes are consistent with the intent of Generic Letter (GL) 8816 which provides guidelines for the removal of cycle specific parameter limits from the Technical Specifications. These changes apply equally to CPSES Units 1 and 2.

Attachment 2 provides a detailed description of the proposed changes, a safety analysis of the changes, and TU Electric's determination that the proposed changes do not involve a significant hazard consideration.

Attachment 3 provides the affected Technical Specification pages (NUREG-1468), marked-up to reflect the proposed changes.

i TU Electric requests approval of this proposed license amendment by February 29, 1996, with implementation of the technical specification changes to occur within 30 days of approval.

In accordance with 10CFR50.91(b), TU Electric is providing the State of Texas with a copy of this proposed amendment.

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9508250247 95o815 DR ADOCK 0500 5 h A Energy Plaza 1601 Bryan Street Dallas, Texas 75201 3411 E

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l TXX 95213. l Page 2 of 2 i

Should you have any questions, please contact Mr. Bob Dacko at (214) 812 8228.

Sincerely, ,

C. L. Terry By: ,

J. J. Kelley. Jr. '

Vice President of Nuclear Engineering and Support BSD/bd Attachments:

Affidavit 1.

2. Description and Assessment

3. Affected Technical Specification page (NUREG 1468) as revised by all approved license amendments

Enclosure:

1. Generic Letter 88 16 c- Mr. L. J. Callan, Region IV Hr. T. J. Polich, NRR Mr. D. F. Kirsch, Region IV Resident Inspectors, CPSES Mr. Arthur C. Tate Bureau of Radiation Control Texas Department of Public Health 1 1100 West 49th Street Austin, Texas 78704 l l

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Attachment 1 to TXX 95213 Page 1 of 1 UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION In the Matter of )  !

)

Texas Utilities Electric Company ) Docket Nos. 50 445 -

) 50 446 ,

(Comanche Peak Steam Electric ) License Nos. NPF-87 Station, Units 1 & 2) ) NPF 89 AFFIDAVIT J. J. Kelley, Jr. being duly sworn, hereby deposes and says that he is Vice President of Nuclear Engineering and Support for TU Electric, the licensee herein: that he is duly authorized to sign and file with the Nuclear Regulatory Commission this Sup)lement One to License Amendment Request 95 03: that he is familiar wit 1 the content thereof; and that the matters set forth therein are true and correct to the best of his knowledge. information and belief.

X J. Kelley, Jr.

Vice President of Nuclear Engineering and Support STATE OF TEXAS )

)

COUNTY OF )

Subscribed and sworn to before me. on this 16th day of osT .

l bdb.bM Notary Public DONALD R. WOOOLAN Nohy M s stote of Tens

'N ' Commission Expires 4+96 I

Attachment 2 to TXX-95213 Page 1 of 6 DESCRIPTION AND ASSESSMENT I. BACKGROUND TU Electric proposes to remove several cycle specific parameter limits from the Technical Specification (TS) and to add these limits to the Core Operating Limits Report (COLR). The addition of these limits to the COLR is a result of the evolution from contractor performed reload analyses (Westinghouse) to TU Electric performed reload analyses. The content of the current COLR was primarily based on the Westinghouse determination of what plant specific parameter limits should be in the COLR to support reload analyses using their methodologies. TV Electric has largely replaced the need for Westinghouse reload methodologies through the development and subsequent NRC approval of TU Electric reload methodologies. Part of the desirability of performing in-house reload analyses is the ability to perform trade offs between operating margins and analytical design margins, whenever appropriate, to optimize the )

economic performance of the plant while maintaining the required margin of j safety. The removal of these parameter limits from the TS and their j addition to the COLR improves the efficiency of this process.  !

The removal of these limits from the TS is consistent with the guidance provided in Generic Letter (GL) 88-16. " Guidance for Technical Specification Changes for Cycle Specific Parameter Limits" (reference 1).

The limits presented in the COLR may be modified, provided the requirements of Specification 6.9.1.6 are met (i.e., the modifications are determined using NRC approved methodologies and meet all applicable limits of the plant safety analysis). The proposed changes result in resource savings for TV Electric and the NRC by eliminating the periodic license amendment requests that would be required for changes to the values of these cycle specific parameters.

' The changes contained in this request are plant specific and did not result from changes recommended in the improved Standard Technical Specifications for Westinghouse Plants. NUREG 1431. The CPSES Technical Specifications remain consistent with NUREG 1431.

II. DESCRIPTION OF TECHNICAL SPECIFICATIONS CHANGE REQUEST The affected Technical Specifications are: ,

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1) 2.1. " Safety Limits" l The proposed changes remove the Reactor Core Safety Limits figures (Figure 2.1-la and Figure 2.1 1b), add appropriate references to the COLR in Specification 2.1.1, and revise the corresponding BASES, (2.1.1 REACTOR CORE) by replacing the reference to Figure 2.1 1 with the title of the figure.

Attachment 2 to TXX 95213 Page 2 of 6

2) 6.9.1.6, " Core Operating Limits Report" The proposed changes modify Specification 6.9.1.6a by adding the removed parameter limits to the list of items contained in the COLR, including a reference to the implementing Technical Specification.

In addition. Specification 6.9.1.6b items 1) and 9) are revised to specify the removed parameter limits and their implementing specification.

The index is revised to delete Figures 2.1-la and 2.1-1b and to repaginate the remaining Section 2 pages.

In summary TV Electric proposes to revise the CPSES Technical Specifications and some of the related BASES by removing the cycle-specific parameter limits for the Reactor Core Safety Limits from the Technical Specifications, adding these parameters to the list of parameter limits in the COLR, and adding the appropriate references to Administrative Controls section of the Technical Specifications.

III. ANALYSIS Recognizing that the accident analyses may change from cycle to cycle, the l NRC issued Generic Letter (GL) 8816 which provides guidelines for the j removal of cycle specific limits of selected parameters from the Technical Specifications. In order to remove cycle specific limits, the Generic Letter requires: (1) the addition of the definition of a named formal report that includes the cycle specific parameter limits that have been established using NRC approved methodology and consistent with all applicable limits of the safety analysis, (2) the addition of an administrative reporting requirement to submit the formal report on cycle-specific parameter limits to the Commission for information, and (3) the modification of individual technical specification sections to note that the cycle specific parameters shall be maintained within the limits provided in the defined formal report.

TU Electric has previously defined the Core Operating Limits Report (COLR), in Specification 1.10, as the appropriate formal report for cycle-specific parameter limits. Appropriate administrative controls requiring the use of NRC-approved methodology and providing the reporting requirements for the COLR have also been previously defined in Specification 6.9.1.6.Section II above and Attachment 3 describe the modifications to the specific affected Technical Specification sections including appropriate references to the COLR.

The figures in the Technical Specifications called the Reactor Core Safety Limits are in fact a series of curves which are developed using NRC approved methodologies. Remaining in the region of acceptable reactor o)eration of these figures ensures that the safety limits established in t1e NRC approved methodologies (e.g., DNBR) are not exceeded. As such, these figures are actually operating limits. These operating limits are

Attachment 2 to TXX 95213 Page 3 of 6 4

in turned used to develop other set points and limits in the Technical Specifications and operating procedures. It is appropriate to revise these operating limits in these figures on a cycle specific basis, using the NRC approved methodologies and safety limits contained therein, to allow for safe and economical operation of the reactor.  :

The cycle specific nature of the parameter limits for the Reactor Core Safety Limits to be removed is discussed below:

The reactor core safety limits, as shown in Figures 2.1-la and 2.1-Ib, define a region of acceptable reactor operation. This region is defined by combinations of reactor power, Reactor Coolant System ,

, (RCS) average temperature, and pressurizer pressure. The acceptable pressurizer pressures are bounded by the pressurizer pressure - high 1 and the pressurizer pressure low reactor trip set points. The region of acceptable core power is plotted as a function of RCS average temperature and pressure and is bounded by the most restrictive of the following limits:

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. the overpower N 16 reactor trip set point:

. the combination of pressure, temperature and power which results in a calculated Departure from Nucleate Boiling Ratio

(DNBR) equal to the DNBR design limit (referred to as DNB limit lines)

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. the combination of pressure, temperature and power which results in boiling at the exit of the reactor vessel (referred to as vessel exit or hot leg boiling lines).

4 The overpower N 16 reactor trip set points are justified through the accident analyses performed for each reload in accordance with Technical Specification 6.9.1.6b. Both the DNB limit lines and the vessel exit boiling lines are dependent on the assumed value of the Thermal Design Flow used for a specific cycle. In addition, the DNB limit lines are dependent on the maximum nuclear enthalpy rise hot channel peaking factor, the cycle specific reference axial power shape, the DNB correlation and DNBR design limit used for a specific core design. The limit on the maximum nuclear enthalpy rise hot channel factor. F%, is currently specified in the COLR: however, for the full benefit of a modification of this limit to be realized, the reactor core safety limits must also be revised. The use of a i particular DNB correlation and DNBR design limit must be in I accordance with the requirements of Technical Specification l 6.9.1.6b: however, several different correlations and limits may be '

approved for use. Thus, depending on the fuel design and the methodology used to analyze a specific core design, the assumptions on the RCS thermal design flow, and the maximum nuclear enthalpy rise. hot channel factor, cycle specific DNB limit lines may be required.

4 Attachment 2 to TXX 95213 Page 4 of 6 Administrative ' Control s Consistent with the requirements of GL 88 16, the Administrative Controls section of the Technical Specifications has been revised to ensure that the removed parameter limits are contained in the COLR, and that those limits are established using NRC approved methodology and are consistent with all applicable limits of the safety analysis.

Summary The limits on the parameters which are removed from the Technical Specifications and added to the COLR must be developed or justified using NRC approved methodologies. All accident analyses, performed in accordance with these methodologies, must meet the applicable NRC-approved limits of the safety analysis. The removal of parameter limits from the Technical Specification and their addition to the COLR does not obviate the requirement to operate within those limits. Furthermore, any changes to these limits must be performed in accordance with Specification 6.9.1.6c. If any of the applicable limits of the safety analyses are not met, prior NRC approval of the change is required, just as is the case for a license amendment request. For the more routine modifications, where NRC approved methodologies and limits of the safety analysis remain applicable, the potentially burdensome and lengthy process of amending the Technical Specifications may be avoided. These changes are essentially administrative and the required level of safety is maintained.

IV. SIGNIFICANT HAZARDS CONSIDERATIONS ANALYSIS TV Electric has evaluated whether or not a significant hazards consideration is involved with the proposed changes by focusing on the three standards set forth in 10CFR50.92(c) as discussed below:

1. Do the proposed changes involve a significant increase in the probability or consequences of an accident previously evaluated?

The proposed changes remove cycle specific parameter limits from the Technical Specifications, add them to the list of limits contained in the Core Operating Limits Report (COLR), and revise the Administrative Controls section of the Technical Specifications.

The changes do not, by themselves, alter any of the parameter limits. The changes are administrative in nature and have no adverse effect on the probability of an accident or on the consequences of an accident previously evaluated. The removal of parameter limits from the Technical Specifications does not eliminate the requirement to comply with the parameter limits.

The parameter limits in the COLR may be revised without prior NRC approval. However Specification 6.9.1.6c continues to ensure that the parameter limits are developed using NRC-approved methodologies and that applicable limits of the safety analyses are met. While

Attachment 2 to TXX 95213 Page 5 of 6 future changes to the COLR parameter limits could result in event consequences which are either slightly less or slightly more severe than the consequences for the same event using the present parameter limits, the differences would not be significant and would be bounded by the requirement of specification 6.9.1.6c to meet the applicable limits in the safety analysis.

Based on the above, removal of the parameter limits from the

. Technical Specifications and the addition of these limits the list of limits in the COLR, thus allowing revision of the parameter limits without prior NRC approval, has no significant effect on the probability or consequences of an accident previously evaluated.

. 2. Do the proposed changes create the possibility of a new or different 1 kind of accident from any accident previously evaluated?

The proposed changes remove certain parameter limits from the Technical Specifications and add these limits to the list of limits in the COLR, removing the requirement for prior NRC approval of revisions to those parameters. The changes do not add new hardware or change plant operations and therefore cannot initiate an event nor cause an analyzed event to progress differently. Thus, the possibility of a new or different kind of accident is not created.

3. Do the proposed changes involve a significant reduction in a margin of safety?

The margin of safety, as it relates to a parameter limit, is the difference between the acceptance criterion for that parameter and its failure value. The proposed changes do not affect the failure values for any system. Through the accident analyses, all relevant event acceptance criteria (as described in the NRC approved analysis methodologies) are shown to be satisfied: therefore, there is no impact on an event acceptance criteria. Because neither the failure values nor the acceptance criteria are affected, the proposed change has no effect on the margin of safety.

Based on the above evaluations, TV Electric concludes that the activities associated with the proposed changes satisfy the no significant hazards consideration standards of 10CFR50.92(c) and accordingly, a no significant hazards consideration finding is justified.

V. ENVIRONMENTAL EVALUATION  ;

TU Electric has evaluated the proposed changes and has determined that the changes do not involve (1) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluent that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure. Accordingly, the proposed changes meet the eligibility criterion for categorical  !

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exclusion set forth in 10CFR51.22(c)(9). Therefore, pursuant to 10CFR51.22(b), an environmental assessment of the proposed change is not required.

3 VI. REFERENCES

1. Generic Letter 88 16 " Guidance for Technical Specification Changes for Cycle Specific Parameter Limits." October 4, 1988 1

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