ML20115G483

Proposed Change 85-04 to Tech Specs,Decreasing Calibr Frequency for Certain Level & Pressure Transmitters Replaced During Recent Outage W/More Reliable Rosemount Transmitters

ML20115G483
Person / Time
Site:	Pilgrim
Issue date:	04/12/1985
From:	BOSTON EDISON CO.
To:
Shared Package
ML20115G474	List: BECO-85-076, Application for Proposed Change 85-04 to License DPR-35, Decreasing Calibr Frequency for Certain Level & Pressure Transmitters Replaced During Recent Outage W/More Reliable Rosemount Transmitters ML20115G483
References
NUDOCS 8504220215
Download: ML20115G483 (3)

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Attachment Proposed Technical Specification Change Calibration Frequency for Certain Rosemount Transmitters l Proposed Change The proposed change involves Pilgrim Nuclear Power Station' Technical Specifications, Appendix A, Table 4.2.F, Minimum Test and Calibration Frequency for Surveillance Instrumentation. It is proposed that the calibration frequency for'the reactor level, reactor pressure, and drywell

' pressure instrument channels be changed from once every 6 months to once each refueling outage. This proposed change is shown on attached Technical l Specification Page'66.

Reason for Change During the recent refueling outage, the existing GEMAC transmitters for the above instrument channels were replaced with Rosemount transmitters. This replacement was made because the GEMAC transmitters are obsolete and replacement parts are unavailable. An advantage of the new Rosemount transmitters is their proven superior performance because of improved accuracy and stability. The proposed Technical Specification change will decrease the minimum required calibration frequency for these instrument channels to take advantage of this expected improvement in performance.

Safety Considerations The proposed change in calibration frequency takes advantage of an expected l

. increase in reliability of these instruments. Because the calibration test is to be performed once each refueling outage without the on-line valving of instruments often required for a 6 month calibration, the potential risk of inadvertent actuation of safety systems is reduced. The instrument check required each shift by Technical Specification Table 4.2.F provides additional assurance of the reliability of these new transmitters.

This change does not involve an unreviewed safety question as defined in 10CFR50.59. It has been reviewed and approved by the Operations Review Committee and reviewed by the Nuclear Safety Review and Audit Committee.

Significant Hazards Considerations It has been determined that the amendment request involves no significant hazards consideration. Under the NRC's regulations in 10CFR50.92, this means-that operation of the Pilgrim Nuclear Power Station in accordance with the proposed amendment would not (1) involve a significant increase in the probability or 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 significant reduction in a margin of safety.

1 8504220215 850412 PDR ADOCK 05000293 P PDR

The NRC has provided guidance concerning the application of standards for determining whether license amendments involve significant hazards considerations by providing certain examples (48 FR 14870). One example of an amendment that is considered not likely to involve a significant hazards consideration is "...(vi) A change which either may result in some increase to the probability or consequences of a previously-analyzed accident or may reduce in some way a safety margin, but where the results of the change are clearly within all acceptable criteria with respect to the system or component specified in the Standard Review Plan." The decrease in the calibration frequency for the reactor level, reactor pressure, and drywell pressure instrument channels is a relaxation of surveillance requirements that is considered to be acceptable because of the improved performance expected of the replacement Rosemount transmitters.

Schedule of Change This_ change will be put into effect upon~ receipt of approval by the NRC.

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PNPS TABLE 4.2.F MINIMUM TEST AND CALIBRATION FREQUENCY FOR SURVEILLANCE INSTRUMENTATION Instrument Channel Calibration Frequency Instrument Check

1) Reactor Level Each Refueling Outage Each Shift

2) Reactor Pressure Each Refueling Outage Each Shift

3) Drywell Pressure Each Refueling Outage Each Shift

4) Drywell Temperature Once/6 Months Each Shift

5) Suppression Chamber Temperature Once/6 Months Each Shift

6) Suppression Chamber Water Level Once/6 Months Each Shift

7) Control Rod Position NA Each Shift

8) Neutron Monitoring (2) Each Shift

9) Drywell/ Torus Differential Pressure Once/6 Months- Each Shift

10) Drywell Pressure Once/6 Months . Each Shift Torus Pressure Once/6 Months

11) Safety / Relief Valve Each refueling Once each day Position Indicator outage (Primary / Secondary)

12) Safety Valve Position Each refueling Once each day Indicator (Primary / outage Secondary)

Amendment No. 66