ML18058A154
| ML18058A154 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 02/03/1992 |
| From: | Slade G CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML18058A155 | List: |
| References | |
| NUDOCS 9202110097 | |
| Download: ML18058A154 (8) | |
Text
consumers Power l'OWERINli
- MICHlliAN'S l'RDliRESS Palisades Nuclear Plant:
27780 Blue Star Memorial Highway, Covert. Ml 49043 February 3, 1992 Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 GB Slade General Manager DOCKET 50-255 - LICENSE DPR PALISADES PLANT - TECHNICAL SPECIFICATIONS CHANGE REQUEST - DELETING THREE PRIMARY COOLANT PUMP TESTING REQUIREMENT The enclosed Technical Specifications change request proposes deletion of a surveillance requirement which will no longer be appropriate due to modifications being made to the Reactor Protective System (RPS) during the upcoming refueling outage.
The subject surveillance requirement verifies the Low Flow Trip setting for non~operating pump combinations.
In addition to the change deleting the surveillance requirement, the format and arrangement of the Safety Limits and Limiting Safety System Settings.
specifications have been revised to enhance the clarity of the subject requirements.
The specified Safety Limits and Limiting Safety System Settings are those requested in our May 30, 1991 and November 1, 1991 Technical Specifications change requests for a changed Variable High Power setpoint and for the Cycle 10 reload, respectively. This change request assumes prior or concurrent approval of those requests.
A revised Basis for Palisades Technical Specification 2.0, "Safety Limits and Limiting Safety System Settings," is also enclosed.
The revised Basis pages correct an error in a paragraph discussing initiating operation with three Primary Coolant pumps and clarify two other paragraphs dealing with three pump operation.
The content, intent, and application of the associated specifications remain unchanged.
The proposed Technical Specifications pages are included as Enclosure 1.
The revised Basis pages are included as Enclosure 2.
The affected existing Technical Specifications and Basis pages, marked to show the changes, are included as Enclosure 3. All pages of each section affected by the changes have been included in each of the enclosures to assist the staff in their review.
9202110097 920203 PDR ADOCK 05000255 p
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A CMS' ENERGY COMPANY t I
The planned modification to the RPS does not alter the ability to perform the surveillance. It does, however, assure that the Low Flow Trip settings for non-operating pump combinations will be verified immediately prior to their use with or without the subject surveillance requirement because setpoint verification is an integral part of adjusting a trip setpoint potentiometer.
In order to assure that these Technical Specifications do not become effective prior to the completion of the RPS modification, it is requested that this change be made effective upon issuance, but no earlier than the end of Cycle 9.
~~
Gerald B. Slade General Manager CC: Administrator, Region III, USNRC NRC Resident Inspector Enclosures 2
CONSUMERS POWER COMPANY Docket 50-255 Request for Change to the Technical Specifications License DPR-20 It is requested that the Technical Specifications contained in Facility Operating License DPR-20, Docket 50-255, issued to Consumers Power Company on February 21, 1991, for the Palisades Plant be changed as described below.
I.
Changes:
A.
It is proposed that reference to footnote (4) be deleted in Table 4.1.1, under item 3, "Reactor Coolant Flow," Surveillance Method c.;
and that footnote (4), in the Notes at the end of Table 4.1.1 also be deleted.
1 B.
It is also proposed that the Safety Limits and Limiting Safety Limits section be administratively revised to enhance clarity and consistency with other sections of the Technical Specifications.
II. Discussion of Changes:
A.
The subject footnote was included in the original Palisades Technical Specifications because all specified RPS Trip settings could not be verified during power operation.
Removal of the Reactor Protective System (RPS) Flow Setpoint Selector Switch (FSSS) eliminates the need for testing the Low Flow Trip setpoints for non-operating pump combinations, as currently required by footnote (4) to Table 4.1.1.
The original design of the RPS provided a single switch (the Flow Setpoint Selector Switch) that selected the proper High Power and Low Flow setpoints for the three available Primary Coolant Pump modes of:
2, 3, or 4 operating pumps.
The trip setpoint for all four channels of both trips were simultaneously changed by electrically selecting the appropriate potentiometer for each channel.
The setpoints which were not selected could not be verified because they were not in the circuit, other pump modes could not be selected while critical:
(selection of setpoints for fewer pumps than currently operating could trip the plant on High Power; selection of setpoints for more pumps than currently operating would cause a trip on Low Flow).
This testing difficulty led to the existing surveillance requirement of Table 4.1.1, footnote (4):
"(4) Trip setting for operating pump combination only.
Settin~s for other than operating pump combinations must be tested during routine monthly testing performed when shut down and within four hours after resuming operation with a different pump combination if the setting for that combination has not been tested within the previous month."
When the RPS was modified to install the_ Variable High Power Trip in 1988 (Amendment 118), the High Power Trip setpoint selection was removed from the Flow Setpoint Selector Switch.
Each Variable High Power channel had its own switch to select the appropriate setting for each pump combination.
The three pump Low Flow Trip setpoints were then conservatively set at a flow value ~reater than achievable with four pumps operating to assure that the 3 Pump" Low Flow Trip settings could not be inadvertently selected; if the Flow Setpoint Selector Switch was moved from the "4 Pump" position, a reactor trip would occur.
II. Discussion of Changes:
Deletion of footnote (4)
(continued)
The testing required by the subject footnote no longer serves to assure that the settings used during three r.ump operation will be correct, but it currently assures that the '3 Pump" position of the Flow Setpoint Selector Switch cannot be inadvertently selected, leaving the plant with reduced Loss of Flow protection. This testing will serve no function with the FSSS removed.
2 The testing of the "3 Pump" settings done "during routine testing while shutdown" is necessary solely to assure that they are conservatively set as described above.
These settings are, of course, in compliance with the allowable "3 Pump" value prescribed in Specification 2.3, "Limiting Safety System Settin~s," which is "~60%
of Primary Coolant Flow With Four Pumps Operating.
The conservative settin~ of the "3 Pump" Low Flow Trip cannot be verified or changed dur1ng operation for the reasons given above.
If the nlant were to operate with only three pumps operatingi the "4 Pump~ potentiometer would have to be adjusted, one channe at a time, to the specified three pump value prior to stopping the fourth Primary Coolant Pump.
Such adjustment of a setpoint inherently includes setpoint verification so the "testin~ within four hours after resuming operation with a different pump comb1nation" required by footnote (4) would be complied with and no additional setpoint verification would be required until the settings were readjusted for four pump operation.
The procedure which would be used for going to, and returning from, three pump operation will be no different with the footnote deleted than it is currently. The steps which would be used for changing from four to three pump operation, for the allowed 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> period, are:
- 1)
- 2)
- 3)
- 4)
- 5)
- 6)
- 8)
- 9)
Reduce reactor power to below the maximum three pump power, Select the "3 pump" maximum for the Variable High Power Trip (one channel at a time},
Reduce the settings of the "4 pump" potentiometer for the Low Flow Trip to the three pump value and verify the setting (one channel at a time).
Stop the desired Primary Coolant Pump.
Within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after stopping the pump, restart the non-operating pump. (Three pump operation is limited to 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> by Table 2.3.l note (4), and Specification 3.1.lb)
Increase the settings of the "4 pump" potentiometer for the Low Flow Trip to the four pump value and verify the setting (one channel at a time).
Select the "4 pump" maximum for the Variable High Power Trip (one channel at a time},
Increase reactor power.
3 II. Discussion of Changes:
Deletion of footnote (4)
(continued)
Removal of the FSSS, leaving a single setpoint potentiometer for each Low Flow channel, will leave no possibility of inadvertently selecting "3 Pump" Low Flow Trip setpoints during power operation, and no further need of the testing required by footnote (4).
Flow setpoint chan~es for differing pump combinations will be accomplished by plac1ng one channel at a time in bypass, adjusting and verifying the setpoint, and returning the channel to service, just as is done currently.
Footnote (4) of Table 4.1.1 contains three requirements:
- 1)
- 2)
- 3)
Setting, for operating pump combination only, tested monthly.
Settings for other than operating pump combinations must be tested during routine monthly testing performed when shut down.
Settings for other than operating pump combinations must be tested... within four hours after resuming operation with a different pump combination if the setting for that combination has not been tested within the previous month.
The first part of the footnote limits the required testing to the setpoints for the operation pump combination.
With the FSSS removed, there will only be one setting for each channel and this part of the note will no longer be needed.
The second part of the footnote, testing all combinations while shutdown, will be unnecessary because there will be no other pre-adjusted settings to verify. It would be possible to adjust each channel setting to the three pump value, verify it, re-adjust it to the four pump value, and verify that, but it would serve no purpose to do so.
It might be noted that the four pump setting, ~95% full flow, also satisfies the three pump setting requirement, ~60% full flow.
Once the FSSS and the "3 Pump" potentiometer are removed, verification of the four pump values would, therefore, fulfill the requirement for testing the three pump setting.
The third part of the footnote, testing the setpoint within four hours after resuming operation with a different pump combination, will be unnecessary because testing is accomplished by the action of setting the trip point for the new pump combination.
The modifyin~ phrase,
- "if the settin~ for that combination has not been tested w1thin the previous month will be inappropriate with the setpoint selector switch removed, since the setpoint would have been altered and the any previous setpoint verification would be void.
Clearly, footnote (4) of Table 4.1.1 will serve no purpose once the FSSS has been removed.
The operation of the plant, including transition to and from three pump operation will be unaffected.
II. Discussion of Changes:
(continued)
B.
The administrative rearrangement of Specification 2.0, "Safety Limits and Limiting Safety Settings," lists those settings proposed in our May 30, 1991 and November 1, 1991 Technical Specifications change requests (Variable High Power setpoint and Cycle 10 reload) in order to present the table as it should appear for Cycle 10.
If either of these prior change requests is disapproved or changed, the setpoints specified in proposed Table 2.3.l should be altered accordingly.
Specifications 2.1, 2.2, and 2.3 were rewritten in the form:
Specification - Applicability - Action.
The information in the existing Objective statement was moved to the Basis.
The Action statements proposed for Safety Limit violation direct the operator to existin~ Administrative Requirement 6.7, "Safety Limit Violation."
The Act1on proposed for failure to meet a Limitin~ Safety System Setting is taken from the Standard Technical Spec1fications, NUREG 0212.
The Basis sections for Specifications 2.1, 2.2, and 2.3 have been separated from the specifications, grouped together, and placed after the specifications.
4 The DNB limits of Safety Limit 2.1 currently appear only in the Basis; they have been moved into the specification itself.
The second and last paragraphs of existing Specification 2.3 contain descriptions of RPS operation and have been moved to the Basis.
The TM/LP trip setting equations, currently presented in the body of the specification have been moved to Table 2.3.1, with the rest of the setpoint limits.
The footnotes of Table 2.3.l have been deleted:
Footnote (1) is redundant to the information provided in the associated Variable High Power setpoint column.
Footnote (2) discusses bypassing of instrument channels. This information is already provided in Specification 3.17, which deals with instrument channel operability.
Bypass information is inappropriate in a setpoint limit table, since it is the channel output, not the setpoint, which is bypassed.
Footnote (3), which gives the minimum TM/LP trip setting, is replaced by the equations which follow the proposed Table 2.3.1, and the minimum setting is discussed in the Basis.
Footnote (4), a 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> limitation on operation with only three Primary Coo1ant Pumps operating is redundant to Specification 3.1.lb, and is inappropriate in a setpoint limit table.
III. Analysis of No Significant Hazards Consideration The first proposed Technical Specifications change, deletion of a surveillance requirement, is requested due to Reactor Protective System modifications which will make the surveillance inappropriate.
The second proposed Technical Specifications change, administratively rearrangin~ the Safety Limits and Limitin~ Safety System Settings specificat1ons (using the limits and sett1ngs proposed in our May 30, 1991 and November 1, 1991 Technical Specifications change requests) is requested to enhance clarity and consistency within the Technical Specifications.
Consumers Power Company finds that activities associated with this change request include no significant hazards; and accordingly, a no significant hazards determination per IOCFR50.92{c) is justified. The following evaluation supports the finding that the proposed change would not:
I.
Involve a significant increase in the probability or consequences of an accident previously evaluated.
5 The deleted surveillance requirement serves only to verify the proper adjustment of an alternate set of Low Flow setpoint potentiometers which could currently be selected by repositionin~ the Flow Setpoint Selector Switch. These alternate setpoint potent1ometers are no longer used.
Prior to implementation of the requested Technical Specifications change, modifications to the Reactor Protective System will have removed both the switch and the alternate setpoint potentiometers. Therefore, the subject surveillance will no longer be useful.
Verification testing of the Low Flow Trip setpoint for the operating pump combination will continue to be accomplished on a monthly interval, as is done with current practice. If the setpoint must be adjusted due to changing the number of operating Primary Coolant Pumps, the setpoint would be verified as part of the adjustment process, as it would be with current practice. Deletion of the subject surveillance requirement will have no effect on the frequency of, or procedure for, verifying the Low Flow Trip setpoints. The subject surveillance requirement affects no other parameters.
The administrative changes do not affect plant operation in any way.
Therefore, the proposed changes do not involve a si~nificant increase the probability or consequences of an accident prev1ously evaluated.
- 2.
Create the possibility of a new or different kind of accident from any accident previously evaluated.
The first proposed change deletes a surveillance requirement which verifies the correct setting of equipment which, since it is no longer used, will be removed from the plant. This change would not alter the operatin~ conditions of the plant systems, and would not reduce the reliability of any plant equipment.
The second proposed change, administrative chan~es to the Safety Limits and Limiting Safety System Settings sect1on, does not affect plant operation in any way.
Therefore, these chan~es do not create the possibility of a new or different kind of acc1dent from any accident previously evaluated.
- 3.
Involve a significant reduction in a margin of safety.
The first proposed change deletes a surveillance requirement which verifies the correct setting of equipment which, since it is no longer used, will be removed from the plant. This change would not affect the setpoints, capacities, or operating limits for any required equipment.
The second proposed change, administrative chan~es to the Safety Limits and Limiting Safety System Settings sect1on, does not affect plant operation in any way.
Therefore, the proposed changes do not involve a significant reduction of a margin of safety.
==
IV. Conclusion:==
The Palisades Plant Review Committee has reviewed this Technical Specifications Change Request and has determined that this change does not involve an unreviewed safety question and that the change involves no significant hazards consideration. This change has been reviewed by the Nuclear Performance Assessment Department. A copy of this Technical SRecifications Change Request has been sent to the State of Michi~an official designated to receive such Amendments to the Operating License.
CONSUMERS POWER COMPANY To the best of my knowledge, information and belief, the contents of this Technical Specifications Change Request are truthful and complete.
By~~-
Davi P Hoffman, Vice re Nuclear Operation Sworn and subscribed to before me this~ day of ~~~
~L~
tary Pubic
- f~Sb~
, Michigan My commission expires t:>/?/9 J..
1992.
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