ML18081A766
| ML18081A766 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 11/19/1979 |
| From: | Lainas G Office of Nuclear Reactor Regulation |
| To: | Schwencer A Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 7912190046 | |
| Download: ML18081A766 (2) | |
Text
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NOV 19 1979 MEMORANDUM FOR:
A. Schwencer, Chief, Operating Reactors Branch #1, DOR FROM:
SUBJECT:
G. Lainas, Chief, Plant Systems Branch, DOR SALEM 1/2: CONTAINMENT PURGE BYPASS CIRCUITS (TAC 08993)
Section A of the Plant Systems Branch has identified the enclosed additional information as being required in order that we can complete our evaluation of the electrical override/bypass aspects of the containment purge matter.
Enclosure:
Request for Additional Information
Contact:
R. F. Scholl... X27l62 cc w/enclosure:
D. Eisenhut W. Gammill E. Reeves
- o. Tandi P. Shemanski E. Adensam B. Ross D. Shum G. Knighton V. Noonan F. Hitt J *. Zudans R. Scholl
\\S\\
G. Lainas, Chief Plant Systems Branch Division of Operating Reactors NRC FORM 318 (9-76) NRCIV' 02.10
REQUEST FOR ADDITIONAL. INFORMATION SALEM NUCLEAR GENERATING STATION UNITS l & 2 CONTAINMENT PURGE OVERRIDE DOCKET NOS. 50-272, 50-311
- 1.
Our review indicates that the switch used to override the automatic Containment Ventilation Isolation (CV!) also defeats the manual isolation signal. It is our position that the overriding of one type of safety actuation signal should not cause the blocking of any other type of safety actuation signal to the isolation valves.
Furthermore, the bypassing of manual initiation is a violation of IEEE Std. 279-1971. Therefore, justify the present design or propose an alternative design that satisfies our concern.
- 2.
We require that instrumentation and controls used for the protection of public health and safety satisfy the requirements for reactor protection systems. Therefore, justify the present design or propose an alternative design for the radiation monitors that initiate containment isolation that sati"sfie~ OlJr requi~eme~tso 0 _
3o Our review also indicates that the safety injection (SI) signal may*be manually reset and blocked such that a subsequent containment pressure high signal or radiation high signal will not activate (VI) retentive memory.
The staff's position in this regard is presented in question l above.
Justify your present design or modify the circuitry so that appropriate safety signals will actuate CVI whenever the protective function is required.
- 4.
We require that sufficient physical features (e.g., key lock switches) be provided to facilitate adequate administrative controls. Describe and justify the features provided or state your intentions for a modified design.
- 5.
We require that system level annunciation of the override status be provided for any safety system impacted when any override is active.
Your destgn does not satisfy this requirement. Describe and justify the features provided or state your intention for a modified design.
- 6.
The Salem plants will monitor (1) the containment atmosphere and (2) the plant stack, for airborne particle iodine and gas activity.
In that these two sets of radiation monitors are not fully redundant backups to each other, we consider each set to be a different source of a required isolation actuation signal.
We require that, should one safety actuation signal be overridden, the other radiation monitoring system should be capable of actuating containment isolation and al~rting the operators to the cause of isolation when a trip level is reached.
Describe and justify the features provided or state your intention for a modified design.