ML20206C373

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Proposed Tech Specs,Supporting Inadequate Core Cooling Instrumentation Sys,Per NUREG-0737
ML20206C373
Person / Time
Site: Fort Calhoun Omaha Public Power District icon.png
Issue date: 03/31/1987
From:
OMAHA PUBLIC POWER DISTRICT
To:
Shared Package
ML20206C296 List:
References
RTR-NUREG-0737, RTR-NUREG-737 TAC-62069, NUDOCS 8704130041
Download: ML20206C373 (5)


Text

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2.0 LIMITISC COMDITIONS FOR OPERATIOM 2.21 Post-Accident Monitoring Instrumentation Applicability Applies to post-accident monitoring instrumentation not included as part of the Reactor Protective System or Engineered Safety Features.

This specification is applicable while in modes 1, 2 and 3.

Objective To assure that instrumentation necessary to monitor plant parameters during post-accident conditions is operable or that backup methods of analysis are available.

Specifications Post-accident instrumentation shall be operable a.4 provided in Table 2-10. If the required instrumentation is not operable, then the appropriate action specified in Table 2-10 shall be taken.

Basis Post-accident monitoring instrumentation provides infomation, during and following an accident, which is considered helpful to the operator in determining the plant condition. It is desirable that this instru-mentation be operable at all times during operation of the plant.

However, none of the post-accident monitors are required for safe shutdown of the plant nor are any control or safety actions initiated by the monitors.

In general, the post-accident monitors provide wide range capabilities for parameters which are beyond the range of normal protective and control instrumentation. They also provide remote sampling and analysis capability to reduce personnel exposure under post-accident conditions. Because the information necessary to assess the effect of an accident (i.e., core damage) can be obtained from other sources and by manual methods, it is not necessary that the post-accident monitors be operable at all times.

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8704130041 870331 ADOCK 05000285 2-97 PDR p PDR Amendment No. 81,/[

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Add The Following To Table 2-10:

7. Reactor Coolant System Subcooled Margin Monitor 2 (E)(F)
8. Core Exit Thermocouples (I) 2/ Core Quadrant (G)(H)
9. Retctor vessel level (HJTC) (J) 2 (K)(L)

Add The Following Footnotes To The Table:

E. With the number of OPERABLE channels one less than the minimum channels operable requirement, either

1. restore the inoperable channel (s) to OPERABLE status within 7 days, or
2. initiate an alternate means of monitoring the subcooled margin, or
3. be in at least HOT SHUTD0WN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

F. With both channels inoperable,

l. restore the inoperable channel (s) to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />, or
2. initiate an alternate means of monitoring the subcooled margin, or
3. be in at least HOT SHUTOOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

G. With the number of OPERABLE channels one less than the minimum channels operable requirement, either restore the inoperable channel to OPERABLE status within 7 days, or be in at least H0T SHUTOOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

H. With both channels inoperable, either restore the inoperable channel (s) to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or be in at least HOT SHUT 00WN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

I. With the number of OPERABLE Core Exit Thermocouples less than the four required by NUREG-0737, either restore to at least four OPERABLE channels within seven days of discovery of loss of operability, or prepare and submit a special report to the Commission pursuant to Specification 5.9.3 within 30 days, out-lining the actions taken, the cause of the inoperability and the plans for restoring the inoperable channel to OPERABLE status.

J. A channel is eight sensors in a probe. A channel is OPERABLE if four or more sensors, two or more in the upper four and two or more in the lower four, are OPERABLE.

K. With the number of OPERABLE channels one less than the minimum channels operable requirement, i

l 1. either restore the inoperable channel to OPERABLE status within 7 days of discovery of loss of operability if repairs are feasible during power operation (MODE 1), or

2. prepare and submit a special report to the Commission pursuant to Specification 5.9.3 within 30 days of discovery of loss of operability, outlining the action tiken, the cause of the inoperability, and the plans for restoring the ch.'nnel to operable status.

L. With both channels inoperable, either restore the inoperable channel (s) to OPERABLE status within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> of discovery of loss of operability if j repairs are feasible during power operation (MODE 1), or s 1. initiate an alternate method of monitoring the reactor vessel inventory, j and I 2. prepare and submit a special report to the Commission pursuant to

! Specification 5.9.3, within 30 days of discovery of loss of operability, j outlining the action taken, the cause of the inoperability and the plans

and schedules for restoring the system to OPERABLE status, and i 3. restore the system to OPERABLE status at the next scheduled Refueling l

Outage.

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DISCUSSION, JUSTIFICATION, AND l PRESENTATION OF NO SIGNIFICANT HAZARDS CONSIDERATIONS

} The inadequate core cooling instrumentation system was installed in the Fort

Calhoun Station pursuant to the requirements of hUREG-0737. Included in the

! implementation requirements for this system was a requirement to submit Technical  !

j Specifications to support and control the operation of the system.

i Accordingly, OPPD prepared, had reviewed by the PRC, and submitted the proposed Technical Specifications to support the inadequate core cooling instrumentation system. Even before submittal of the proposed Technical Specifications, an j agreement as to the scope of the Specification with regard to core exit thermocouples i was achieved between the OPPD staff and the NRC Project Manager. The agreement

{ concerning this pirticular portion of the Specification was viewed as essential to the ability of the Station to be able to effectively implement the new requirements.

Correspondence concerning the core exit thermacouples (CET's) was docketed and primarily concerned the problems experienced with MI (Mineral Insulated) cables associated with the system.

. The proposed Technical Specificatiens were developed along the same format I as that existing in Table 2-10. This primarily means that the item is noted, t

) along with the minimum operable channels requirement, followed by one or more i footnotes specifying the associated action statements (s) that apply. The Fort Calhoun Station Technical Specifications do not, unlike the Standard Technical Specifications, contain a Specification of " required number of channels."

) The next version which was discussed with the NRC Reviewer was based upon this

! requirement for a Specification " required number of channels." In order to  ;

l rectify the situation, a statement concerning required number of channels is [

included as a footnote to Table 2-10, (item (I)). Item (I) requires a special j report be submitted within 30 days if the number of operable channels falls
below the required number of channels for greater than 7 days. We believe i this will acceptably resolve the reviewer's concern.

l The Specification for the Reactor Coolant System subcooled margin monitor has

been altered slightly from the version previously submitted for your review

] and approval.

I The time limits in the liriting condition for operation are consistent with j those previously sent. However, as alternate means exist for the calculation  ;

. of the subcooled margin, (separate from the calculation done via the " inadequate l core cooling system instrumentation"), an additional alternative plant shutdown was added. The action statements (as noted in footnotes E and F), allow for i restoring the inoperable channel (s) to operable status within x number of days / hours,

! or initiating an alternate means of determining the subccoled margin, or initiating

a plar.t shutdown within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

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The remainder of the Specifications remain as they were discussed previously.

It should be noted that the most recent version of the Table 2-10, which was not acceptable to the reviewer, was returned to its previous configuration (without the column for required number of channels). OPPD believes that the footnotes fulfill the same function as two columns, and do not impose a' different format on this Table than all others in the Technical Specification.

Pursuant to the requirements of 10 CFR 50.92, the proposed changes to the Technical Specification were previously assessed to determine if there was potential for a significant hazards finding. The discussion is only included here for completeness.

Will the proposed change increase significantly the probability or consequences of any accident of malfunction of equipment previously evaluated in the Safety Analysis Report?

No, the implementation of the proposed changes would not significantly increase the probability or consequences of any accident previously evaluated. The inadequate core cooling instrumentation system was installed in order to provide for the post accident monitoring of the condition of the reactor core. The systems themselves only serve in a monitoring capacity, and do not directly control any automatic function associated with the accident. Failure of any portion of the system would be, first of all, controlled by the added limiting conditions for operation, assuring that the operations Staff is aware of the requirements of the system. Additionally, the failure of the system would have no impact on the course of any accident previously analyzed in the Safety Analysis Report. By adding limiting conditions for operation,cthe likelihood of any accident occurring with the system unavailable due to various reasons if no operability requirements were imposed is lessened.

Will the proposed change in any way create the possibility for a new or different accident than any previously analyzed in the Safety Analysis Report?

No, since the proposed change is only intended to impose operability requirements on an existing system. The imposition of these requirements in no way creates any new or different accidents than those previously included in the Safety Analysis Report.

Does the proposed change significantly reduce the margin of safety as defined in the basis of the Technical Specifications?

No, because this change is intended to impose operabiltiy requirements on the inadequate core cooling instrumentation system. It does not lessen any requirements of the existing Technical Specifications, and hence does not reduce the margin of safety.

For the above reasons, the Omaha Public Power District does not believe that the proposed changes to the Technical Specifications involve any significant hazards considerations.