ML19294B504
| ML19294B504 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 02/11/1980 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML19294B503 | List: |
| References | |
| NUDOCS 8003040155 | |
| Download: ML19294B504 (2) | |
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ENCLOSURE SAFETY EVALUATION ELECTRICAL, INSTRUMEliTXTION AND CONTROL ASPECTS OF THE BROWNS FERRY, UNITS 1 & 2 PROPOSED TECHNICAL SPECIFICATION CHANGES REGARDING LOW PRESSURE TODMIT INJETTION (LPCI SYSTEM MODIFICATIONS INTRODUCTION By letter dated May ll, 1979, NRC issued Amendment Nos. 51 and 45 to Facility License Nos. DPR-33 and DPR-52 for the Browns Ferry Nuclear Plant, Units 1 and 2.
These amendments authorized the licensee to change the power supply for certain low pressure coolant injection valves and are related to earlier amendments (Nos. 27 to License DPR-33 and 24 to License DPR-52) which dealt with the elimination of the LPCI system's recirculation loop selection logic.
The licensee (TVA) committed, by letter dated June 15, 1977, to submit the proposed Technical Specification changes concerning the LPCI modifi-cations with the reload amendment request for each unit.
This request was submitted by TVA letter dated Octcber 4,1979.
EVALUATION We have reviewed these proposed changes to pages 97,111,112,182, and 221 of the Browns Ferry Nuclear Plant Technical Specifications for Unit Nos.1 and 2, which are as follows:
1.
The change to Table 4.2.B (Surveillance Requirements for Instrumentation that Initiate or Control the CSCS) removes the surveillance requirenents on four reactor pressure sensors (PS-3-186A&B, and PS-3-187A&B) whose sole function was that of a pennissive in the LPCI recirculation loop selection logic.
2.
The changes to pages 111 and 112 remove the low reactor water level instrumentation as the source of a LPCI loop selection logic initiation signal.
3.
The changes to Section 3.6.F (Limiting Conditions for Operation) and the corresponding bases removes the limitations placed on variation in speed between the recirculation pumps.
The nurp ' of this limitation was to prevent the LPCI loop selection logic from selecting the wrong loop for injection which was possible for certain low probability accidents with the recirculation loop operating at large speed differences.
8003040 /
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- Since the LPCI loop selection logic has been removed from the Broi i Ferry Nuclear Plant, Unit Nos. I and 2, there is no longer the nr..d for surveilli.nce requirements relating to this logic nor the need to limit the variation of recirculation pump speed for purposes associated with this logic.
CONCLUSION Based on our review, we conclude that the Electrical, Instrumentation, and Control (EI&C) aspects of the proposed Technical Specification changes for the Browns Ferry Nuclear Plant, Unit Nos.1 and 2, are consistent with our safety evaluation of May 8,1978 (enclosure to nemo from W. Butler to G. Lear) regarding this subject and since the LPCI loop selection logic has been removed, we find the proposed Technical Specification changes acceptable.