NRC-98-0003, Application for Amend to License NPF-43,revising Tech Specs to Improve Administrative Controls Re thermal-hydraulic Stability & Idle Recirculation Loop Startup & Eliminating Neutron Flux Indication from TS

Application for Amend to License NPF-43,revising Tech Specs to Improve Administrative Controls Re thermal-hydraulic Stability & Idle Recirculation Loop Startup & Eliminating Neutron Flux Indication from TS

ML20199H920
Person / Time
Site:	Fermi
Issue date:	01/28/1998
From:	Gipson D DETROIT EDISON CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20199H924	List: ML20199H937 NRC-98-0003, Application for Amend to License NPF-43,revising Tech Specs to Improve Administrative Controls Re thermal-hydraulic Stability & Idle Recirculation Loop Startup & Eliminating Neutron Flux Indication from TS
References
CON-NRC-98-0003, CON-NRC-98-3 GL-94-02, GL-94-2, IEB-88-007, IEB-88-7, NUDOCS 9802050154
Download: ML20199H920 (14)

Text

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Douglas R. Gipson Senior Vice President, Nuclear Seneration Fermi 2 f@) North Dixie llwy, New1mrt, Mic higan eliW Tt1:9133861,201 Fab 3131&4172 Detroit Edison January 28,1998 NRC 98-0003 U, S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D C 20555

References:

1) Fermi 2 Docket No. 50-341 NRC License No. NPF-43

2) NRC Generic Letter 94-02,"Long-Term Solutions and Upgrade ofInterim Operating Recommendations for Thermal-Hydraulic Instabilities in Boiling Water Reactors", dated July 11,1994

3) Detroit Edison letter to NRC, NRC-94-0089, " Detroit Edison Response to NRC Generic Letter 94-02", dated September 8, 1994

4) Detroit Edison letter to NRC, NRL'-97-0105, " Proposed Technical Specification Chac# (License Amendment)-

Neutron Monitoring System", dated December 10,1997 4-

5) BWROG Letter 94078,"BWR Owners' Group Guidelines for Stability Interim Corrective Action", dated June 6,1994

6) NRC Letter Boger to Tully,"NRC Evaluation of BWR ,

Owners' Group Topical Report NEDO-31558, Position on NRC Regulatory Guide 1.97, Revision 3, Requirements for Post-Accident Monitoring System", dated January 13,1993 1 <

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7) NRC Letter Colburn to Gipson," Regulatory Guide 1.97 - f '

g" :'>' "7"*' 3 Boiling Water Reactor Neutron Flux Monitoring - Fermi 2",

dated February 17,1994

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8) NRC Letter Colburn to Gipson," Regulatory Guide 1.97 -

Boiling Water Reactor Neutron Flux Monitoring MPA A-17",

dated May 10,1993

9) GE Nuclear Energy Letter, Lim to Thorson," Fermi 2 Recirculation Operating Loop Drive Flow Limit Prior to Idle Pump Restart, MIIL96009, daad January 29,1996

10) NUREG-1433, " Standard Technical Specifications, General Electric Plants, BWR/4", Revision 1, April 1995.

I1) NEDO-31960-A,"BWR Owners' Group Long-Term Stability Solutions Licensing Methodology," dated November 1995

Subject:

Proposed Technical Specifict. tion Change (License Amendment)-

Thermal-Ilydraulic Stability, idle Recirculation Loop Startup, and Post Accident Monitorine Pursuant to 10CFR50.90, The Detroit Edison Company (Detroit Edison) hereby files an application to amend the Fermi 2 Technical Specifications (TS). The proposal revises the Technical Specifications to improve the administrative controls related to thermal-hydraulic stability and idic recirculation loop startup, and eliminates neutron flux indication from the TS post-accident monitoring parameters.

Enclosure 1 provides a description and evaluation of the proposed changes.

Enclosure 2 provides an analysis of the significant hazards consideration assessment using the standards in 10CFR50.92.

Enclosure 3 provides marked up pages of the existing Technical Specifications to show the proposed changes and a typed version of the affected Technical

. Specification pages with the proposed changes incorporated.

As described in Reference 4, Detroit Edison plans to install the new Power Range Neutron Monitoring (PRNM) System during the sixth refueling outage (RFO6). As also discussed in Reference 4, the Stability Option III automatic trip will be installed during RF06 in th: ' indicate only" mode. Assuming successful operation of the system in the fbilowing operating cycle, the automatic trip would be activated during the seventh refueling outage (RFO7). The proposed Technical Specification changes related to the PRNM hardware changes are provided in the Reference 4 request. Part of the enclosed TS changes address the administrative controls for the interim period prior to the activation of the Option 111 trip. Technical Specification changes for the activation of the Option 111 trip will be submitted separately in time for the scheduled activation during RFO7, currentiv planned for the spring of the year 2000.

The enclosed thermal-hydraulic subility changes are being proposed separately from the Reference 4 Power Range Neutron Monitoring (PRNM) System TS changes

I USNRC i NRC-98-0003  !

Page' I because the changes are not directly related to the PRNM hardware change or the  ;

associated General Electric Licensing Topical Report. In addition, it is the intent that the enclosed changes be implemented prior to the PRNM hardware changes to enhance thermal-hydraulic stability controls in the interim period until the automatic trip function is installed in RFO7. Because the proposed license amendment represents enhanced administrative controls ulated to thermal-hydraulic stability, approval is requested as soon as practical. The changes will be implemented within 60 days of approval.

Detroit Edison has evaluated the proposed Technical Specifications against the criteria of 10CFR50.92 and determined that no significant hazards consideration is involved. The Fermi 2 Onsite Review Organization has reviewed and recommended approval of the proposed TS changes. The Nuclear Safety Review Group has reviewed the proposed changes and concurs with the enclosed determinations. In accordance with 10CFR50.91, Detroit Edison is providing a copy of this letter to the State of Michigan.

If you have any questions or comments, please contact Mr. Joseph Conen of my staff at (734) 586-1960.

Sincerely, ,

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Enclosures cc: A. B. Beach B. L. Burgess G. A. Harris A. J. Kugler Supervisor, Electric Operators, Michigan Public Service Commission

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I, Douglas R. Gipson do hereby affirm that the foregoing statements are based on facts and circu:nstances that are true and accurate to the best of my knowledge and belief.

M Douglas R,tiipson

- Senior Vice President <

Nuclear Generation On this- day of - M//d fi[1998 before me personally .

july swornfnd seys that he executed the appeared Douglas R. Gipson being first[

- foregoing as his free act and deed.

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Enclosure I to NRC-98 0003 Page1-

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ENCLOSURE 1 FERMI 2 NRC DOCKET NO 50-341 OPERATINL LICENSE NPF-43 REQUEST TO REVISE TECilNICAL SPECIFICATIONS:

THERM AL-ilYDRAULIC STAHILITY, IDLE RECIRCULATION LOOP STARTUP, AND POST-ACCIDENT MONITORING DESCRIPTION AND EVALUATION OF TIU, PROPOSED CliANGES

Enclosure I to -

NRC-98-0003 '

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- BACKGROUND As discussed in Reference 4, Detroit Edison is planning to replace the power range monitor portion of the Neutron Monitoring System with a GE digital NUMAC Power Range Neutron Monitoring (PRNM) retrofit system. The new equipment will ultimately

. include capability for an automatie Oscillation Power Range Monitor (OPRM) trip to 4

detect and suppress possible thermal hydraulic instabilities in the plant. The new OPRM trip function, when enabled, will implement the Boiling Water Reactor Owners Group (DWROG) defined " Stability Option 111" alternative (Reference 11;. Ilowever, the OPRM trip function will not be enabled during the first cycle of operation with the new equipment. This proposed Technical Specification (TS) change request is being submitted to provide improved administrative controls for thermal-hydraulic stability during the phased implementation of(PRNM) System changes.

Detroit Edison is proposing the following three specific TS changes associated with thermal hydraulic stability and post accident monitoring:

A, Changes to prohibited and restricted operating regions, Limiting Condition for Operation (I.CO), Actions, Surveillance Requirements and Bases in the Core Thermal llydraulic Stability Specification consistent with NRC Generic Letter 94-02 (TS 3.4.10, Figure 3.4.101, and B 3/4.4.10).

B. Stabilit/ related improvements in the operating restrictions in the Idle Recirculation Loop Startup Specification (TS 3.4.1.4, Figure 3.4.1.4-1, and B3/4.4.1).

C. Elimination of Neutron Flux from parameters required to be monitored by Post Accident Monitoring TS, as allowed by References 6 and 7 (Tables 3.3.7.5-1 and 4.3.7.5-1)

Each of these changes are individually evaluated in the Evaluation section of this submittal.

EVALUATION A. Changes to prohibited and restricted operating regions, LCO, Actions, Surveillance Requirements, and Bases in the Core Thermal Hydraulic Str. oil ty

- Specification ' consistent with NRC Generie Letter 94-02 (TS 3.4.10, Figure 3.4.10-1, and B 3/4.4.10).  ;

Chances to Prohibited and Restricted Operatina Recions:

~ The proposed change modifies the current restrictions on operating at power levels and

. ' core flow levels that are designed to avoid core thermal hydraulic instabilities Associated bases are also being revised. The current TSs are based upon the guidance of Ctt Service Information Letter (SIL) 380, Revision 1 and NRC Bulletin 88-07, Supplemert 1. The proposal updates the restrictions to include the additional interim corrective r.ctions

. Detroit Edison has taken in response to NRC Generic Letter (GL) 94-02 (Reference 2).

Enclosure 1 to >

NRC-98-0003 Page 3 In response to GL 94 02, the Boiling Water Reactor (BWR) Owners' Group (BWROG) issued Reference 5 to previde improved guidelines for stability interim corrective actions.

Reference 3 provided Detroit Edison's response to GL 94-02. Detroit Edison committed to modifying operating procedures and updating training to be consistent with the BWROG guidance. Implementation of the guidance in this proposed change is consistent with the actions already taken.

Chances to Ficure 3.4.10 1; TS Figure 3.4.10-1, " Thermal Power versus Core Flow" has been modified to show new Scram, Exit, and Stability Awareness Regions in terms of percent rod line, core flow and thermal power. The new regions are intended to replace references to Regions A and B, as well as the previous region of rurveillance applicability (Greater than 30% of RATED THERMAL POWER and Core Flow less than 50% of Rated Core Flow). Since these Stability Region boundaries are based on Rod Lines (lines of constant control rai configuration on n oower/ flow map), the applicable Rod Line representations have been re-computed fu % Figure. The re-computed Rod Line representations are consistent

- with empirical dam taken along the 100% Rod Line during both recent and historical startup testing.

The change to the nomenclature of stability regions from Region A and B to the Scram and Exit Regions respectively,is consistent with the latest BWROG Guidance. For the proposed revision to Figure 3.4.10-1, the Scram Region boundaries remain the same as Region A, but the Exit Region Boundaries are larger than Region B, providing additional stability margin. The figure was also revised to show core flow starting at 30 percent rated core flow as opposed to the present 20 percent rated core flow. This change was made to improve the readability of the figure since core !'ows less than 30 percent are not possible over the rod lines ofinterest.

Chances to Limitine Condition for Ooeration (LCOh The new Limiting Condition for Operation statement that the reactor core shall not exhibit coie thermal hydraulic instability is to ensure that the LCO is broad enough so that the guidance of ACTION 3.4.10.c to scram the reactor when an instability occurs remains applicable when in any region and not only when in the Exit Region.

Chances to ACTION:

Changes to ACTION 3.4.10.a are intended to reflect the new nomenclature adopted for -

Region A as discussed above.

Changes to ACTION 3.4.10 b are intended to reflect the new nomenclature adopted for Region B as discussed above. Leaving the Exit Region by a core flow increase is permitted in addition to leaving the region by control rod insertion. A new footnote states that Restarting an Idle Recirculation Loop or resetting a Recirculation Flow Limiter are lot acceptable means ofimmediately increasing core flow to leave the Exit Region. This footnote is intended to prevent delays in leaving the Exit region that might typically be

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Enclosure 1 to r -

NRC-98-0003 .

Page 4 ~ -

f associated with these activities, because execution of these activities could not be -

f completed in a short enough time to be considered immediate. A' core flow increase will result in establishing a more stable power / flow relationship with respect to thermal-

hydraulic instability, and thus is an acceptable means to leave the Exit Region.;  ;

Changes _to ACTION 3.4.10.c have been made to eliminate a tie between completing a  :

manual scram in the event an instability is detected and operation in Region B (now the j Exit Region). The new ACTION 3.4.10.c new clearly require: a manual scram whenever instability is detected, regardless of what region the reactor is operating within. In- ,

addition, the definition of what constitutes an mstability has been revised to reflect the i yatest BWROO guidance, and is intended to be able to describe reactor / nuclear instrumentation behavior at the onset ofinstability, This contrasts with the existing TS

, guidance,7which is more representative of conditions where a fully developed instability is in progress.' The 'mprovements to ACTION 3.4.10.c will result in appropriate manual i

, protective actions being applicable over a larger operating region and at a more

, appropriate time. ,

Channes to Surveillance Reauirements -

The change to the Surveillance Requirements (SR) reflect a more appropriate action to be ,

taken when operating near Region B (now the Exit Region). The revised Surveillance requirement would require an immediate and periodic (once every hour) assessment of reactor stability by monitoring the nuclear instrumentation for signs ofinstability. This guidance is appropriate for operation near the Exit Region, resulting in early detection of any instability that might occur, and provides superior protection against instability F compared to the existing TS guidance to check on a 4 hourly basis that the reactor core is

- not operating in Region A or B. The current SR does not account for the potential for

- instability when operating outside Region B (now the Exit Region), while the new guidance requires that_the reactor be assessed for stability when operating near the Exit l ' Region. The change to the region of applicability for the Surveillance Requirement is in accordance with the latest BWROO guidance and bounds the Exit Region by 5% in core ,

l flow and Rod Line. The shape of this new Stability Awareness Region is intended to resemble the shape of the Scram and Exit Regions in that all three region boundaries are

. loosely based on predicted lines of constant Core Decay Ratio (a measure of stability of an .

1 oscillating system).1The new Stability Awareness Region does not bound the cunrent i

region of surveillance applicability in all areas since the current region was based on Jsimplicity not on predicted lines _of constant Core Decay Ratio. While the proposed

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. Stability Awareness Region is smaller than the existing surveillance region, it does N Jprovide an extension to the current region of surveillance applicability at high Rod Lines -

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up to 55% Core flow to support the concept of a line of constant Core Decay Ratio.

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Enclosure 1 to NRC-98-0003 Page5 Chances to BASILS Changes to the BASES section support the changes in nomenclature from Regions A and B to tt.: Scram, Exit and Stability Awareness Regions and to reflect that core flow increases, within appropriate limitations, are pem;issible for leaving the Exit Region.

Changes were made to reflect knowledge gained from instability events that occurred outside Regions A and B. Specifically, while rare, the potential exists for instabilities to occur near the Exit Region boundary, and low Xenon concentration can be a factor in creating conditions where instability can occur Reactor pressure is also a contributing factor, but has a second order effect when compared to Xenon concentration, subcooling and power distribution.

Changes were aiso made to reflect knowledge gain:d in the development of hardware based solution trip algorithms as to the impact of even small instabilities on the Safety Limit Minimum Critical Power Ratio (SLMCPR). This includes the need to scram for any instability, whether core wide or regional, in order to protect the SLMCPR.

In summary, these proposed changes are consistent with the industry developed guidelines for avoiding instabilities and are in agreement with the requirements in GL 94-02.

H. Stability related improvements in the operating restrictions in the Edle

. Recirculation Loop Startup Specification (TS 3.4.1.4, Figure 3.4.1.4-1, and B 3/4.4.1).

The proposal eliminates redundant provisions in TS Section 3.4.1.4 related to power and core flow operating regions where an Idle Recirculation Loop Startup is permitted because these restrictions are functionally redundant to those specified in 'IS Section 3.4.10.

Associated bases are also being changed. This includes deleting text in TS 3.4.1.4 and deleting TS Figure 3.4.1.41. In addition, the TS Section 3.4.1.4 requirement to reduce the operating loop flow to less than or equal to 50% of rated loop flow prior to starting an idle loop is being eliminated. This change is proposed because compliance with this

. specification requires operation at low core flows where core thermal-hydraulic stability can be a concern and the original e,eneric bases for this specification are no longer appropriate. The original genaric bases were related to scram avoidance and jet pump riser brace vibration (Reference 9). The following provides a discussion of these bases.

Scram Avoidance Bases: The scram avoidance bases were related to the neutron flux spike seen during idle loop startup and reduced margin to the APRM flow biased neutron flux scram from single pump operation due to lower measured drive flow. Detroit Edison

' does not use an APRM flow biased neutron flux scram, but instead employs an APRM flow biased simulated thermal power scram utilizing a filter circuit with a time constant of approximately 6 seconds to filter de neutron flux signal. In addition, Detroit Edison also employs ajog circuit on the recirculation pump discharge valves that results in a less severe APRM response to the idle loop restart transient. The combination of the less

- severe idle loop restart APRM response and APRM scram setpoints that are based on a

' Enclosure 1_to

_NRC-98 0003 Page 6 :

filtered neutron flux signal eliminates any need to reduce core thermal hydraulic stability margin to gain margin for APRM scram avoidance orjet pump riser brace vibration by lowering operating loop flow to less than or equal to 50% of rated loop flow prior to an idle loop startup (Reference 9).

Jet Pumn Riser Brace Vibration Bases: This bases :s related from an experience with an earlier BWR plant where restrictions were imposed due to a concern about jet pump riser brace vibration. The riser brace loads increased with the amount of flow mismatch between the two recirculation loops that occurred following the restart of the idle pump.

When returning to two loop operation from single loop, the transition would have been through the mismatch cpeed zone if the operating loop was allowed to be at greater than 50% speed. To avoid this, the operating loop flow had to be lowered to 50% before starting the idle loop. Riser braces were modified for later plants, including Fermi 2:

therefore, these restrictions are unnecessary at Fermi 2. Furthermore, the flow mismatch resulting from restart of the idle pump is adequately addressed by requirements in the Fermi 2 Technical Specifications 3.4.1.3 (Reference 9).

4 Tnese changes are also consistent with the BWR Improved Standard Technical Specification, NUREG-1433, Rev.1 (Reference 10).

C. Elimination of neutron flux from parameters required to be monitored by Post Accident Monitoring Specification as allowed by Reference 6 (TS Tables 3.3.7.5-1 and 4.3.7.5-1).

The proposed change eliminates Neutron Flux instrumentation from the list of required post accident monitoring instrumentation contained in TS Tables 3.3.7.5-1 and 4.3.7.5-1.

The basis for this change is that Neutron Flux instrumentation was determined not to be Category I instrumentation for BWRs (as defined in NRC Regulatory Guide 1.97). Since the purpose of the post accident monitoring TS is to assure that instrumentation critical to post accident operations (Category I instrumentation) is available, the Neutron Flux

- instrumentation does not need to be included in the scope of this TS.

The NRC, in a letter dated May 10,1993, (Reference 8) requested Fermi to review their neutron flux monitoring instrumentation against the criteria of NEDO-31558 and provide a letter to the NRC documenting results of the review. This letter also informed Detroit Edison that neutron flux monitoring instrumentation for BWRs is no longer considered Category I instrumentation and that Fermi could request removal of the neutron flux monitoring instrumentation from the post-accident monitoring technical specifications if the system met the attemate criteria proposed in NEDO 31558. Detroit Edison responded by submitting results of the review to the NRC in a letter dated September 28,1993.

From this, the NRC concluded thati1) the deviations from NEDO-31558 are acceptable and 2) the post-accident neutron flux monitoring instrumentation at Fermi 2 is an

_ acceptable attemative to the guidance of RG 1.97 Category I criteria. This conclusion is documented in a letter dated February 17,1994 (Reference 7).

Based upon the above, the proposed change is acceptable.

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NRC-98-00031 ,

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SIGNIFICANT HAZARDS CONSIDERATION

- In accordance with 10CFR50,92,~ Detroit Edison has made a determination that the J

,x  : proposed amendment involves no significant hazards considerations. -To nnke thisi i' ' determination, Detroit Edison must establish that operation in accordance with the

. proposed amendment would not: (1) involve a sirJScant Increase in the probability or - 1 L = . consequences of an accident previously evaluated; or (2) create the possibility of a new or' different kind of accident from any accident previously evaluated; or (3) involve a Lsignificant reduction in a margin of safety. The significant hazards consideration -

assessment is presented in Enclosure 2.-

ENVIRONMENTAL _IMPACI Detroit Edison has reviewed the proposed Technical Specification changes against the

. criteria of 10CFR51.22 for environmental considerations. The proposed change does not-1

- involve a significant hazards consideration, nor significantly change the types or

- significantly increase the amounts of ellluents that may be released offsite. In addition the proposed changes do not involve a significant increase in individual or cumulative occupational radiation exposures. Based on the foregoing, Detroit Edison concludes that

_ the proposed TS meet the criteria given in 10CFR$1.22(c)(9) for a categorical exclusion F from the requirements for an Environmental Impact Statement.

b CONCLUSION

. Based on the evaluation abovei 1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and 2) such

- activities will N ccaducted in compliance with the Commission's regulations, and

. proposed amendments will not be inimical to the common defense and security or to the health and safety of the public.

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- Enclosure 2 to NRC 98 0003 .

Page1 a

I ENCLOSURE 2 ,

I FERMI 2 i NRC DOCKET N>-341 OPERATING LICENSE NPF-43 REQUEST TO REVISE TECIINICAL SPECIFICATIONS:

10CFR50.92 EVALUATION BASIS FOR SIGNIFICANT HAZARDS DETERMINATION:

The proposed Technical Specification changes described in Enclosure 1 do not involve a significant hazards consideration. This determination was reached by evaluating: 1) the changes to TS 3.4.1.4 and 3.4.10 associated with thermal hydraulic stability and idle recirculation loop startup, and 2) the changes to fS 3/4.3.7.5 associated with post-accident monitoring. These evaluations are provided below:

Thermal Hvdraulle Stability and Idle Recirculation Loon Startup:

1. The proposed TS changes do not involve a significant increase in the probability or consequences of an accident previously evaluated.

These changes act to nrohibit operations which have been found to carry a significant potential for the fonnation of core thermal-hydraulic instabilities and eliminates inappropriate technical specifications for maintaining <50%

- recirculation loop flow before starting the idle recirculation pump. As such, operation in compliance with the proposed provisions does not affect any initiating mechanism for nreviously evaluated accidents or the response of the plant to a 4

previously evaluated accident. The actions taken lead to placing the plant in a safe condition and are not themselves associated with an initiator for a previously

. evaluated accident. Therefore, the change does not represent a significant increase

- in the probability or consequences of any previously evaluated accident.

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Enclosure 2 to NRC-98-0003 Page 2

2. The proposed TS changes do not create the possibility of a new or different kind of accident from any accident previously evaluated.

As discussed above, the change acts to restrict opecations previously allowed. The change also provides remedial actions that act to place the plant in a safe condition.

The actions specified are within the analyzed domain of plant operations. Unless an instability event is in progress, the new allowance to ise a core flow increase to leave the Exit Region is no different than normal plant maneuvering. If an instability event is in progress, the new ACTION 3.4.10.c to scram the reactor takes precedence. The allowance to start an idle loop with the active loop flow >50% of rated flow has been shown to have no adverse affect on scram avoidance orjet pump riser brace vibration. Therefore, the pioposed changes do not create a new or different type of accident.

3. The proposed TS changes do not involve a significant reduction in a margin of safety.

Consistent with the latest BWROG guidance, the changes act to expand the Exit region compared to the current TS for core thermal-hydraulic instability at.d provide improved remedial actions which promptly terminate the potential for instability. These changes therefore do not involve a significant reduction in a margin of safety.

Post-Accident Monitorine:

1. The Troposed TS changes do not involve a significant increase in the probability or consequences of an accident previously evaluated.

The proposed change does not involve a change in plant design or a change in the manner in which the plant is operated. The long term post-accident design requirements of the Neutron Monitoring System (NMS) are not based on operator use for transients with scram, accidents with scram, and other occurrences without scram (Reference 6). For lesser events such as transients without scram, the NMS enhances the operator actions, since successful verification that power is below approximately 3% power can avoid non-routine operator actions (Reference 6).

These lesser events establish design requirements for the NMS. The failure of tids instrtunentation during post-accident conditions will not prevent the operator from determining reactor power levels. Alternate parameter status will be available from which reactor power may be inferred. Based on the multiple inputs available to the i operator, sufficient information will be available upon which to base operational

decisions and to conclude that reactivity control has been accomplished. This change will therefore not represent a significant increase in the probability or consequences of an accident previously evaluated.

Enclosure 2 to NRC 98-0003 Page 3

2. The proposed TS changes do not create the possibility of a new or different kind of -

acciden: from any accident previously evaluated.

The proposed change does not introduce a new mode of plant operation and does not involve the installation of any new equipment or modifications to the plant.

Therefore, it does not create the possibility of a new or different kind of accident from any accident previously evaluated.

3. The proposed TS changes do not involve a signincant reduction in a margin of safety.

The proposed change eliminates a TS listing of a function to reflect the actual safety signincance. As such it has no effect on actual plant operation and thus no impact on any margin of safety.

Based on the above, Detroit Edison has determined that the proposed amendment does not involve a signincant hazards consideration.

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