ML20035E732
| ML20035E732 | |
| Person / Time | |
|---|---|
| Issue date: | 03/25/1993 |
| From: | Chilk S NRC OFFICE OF THE SECRETARY (SECY) |
| To: | Taylor J NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO) |
| References | |
| FRN-57FR14514, REF-10CFR9.7, REF-GTECI-B-56, REF-GTECI-EL, TASK-B-56, TASK-OR AE06-1-021, AE6-1--21, AE6-1-21, GL-94-01, GL-94-1, NUDOCS 9304190164 | |
| Download: ML20035E732 (2) | |
Text
-
-.......................[.,
- - - ^ -
^~
RELEASED TO THE PDR l
/
h/3/Qd M,
f re UNITED STATES l
[
NUCLEAR REGULATORY COMMiylVN /g);g I jp gjg
{!
i WASHINGTON. D.C. 20555 t
e
.e.eeoeeee.eeeee e,,,eoe Os G
,P*
...e+
March 25, 1993 OFFICE OF THE SECRETARY MEMORANDUM FOR:
James M. Taylor Executive Director for Op ations FROM:
Samuel J. Chilk, Secreta '
l
SUBJECT:
SECY-93-044 - RESOLUTIONlOF ENERIC SAFETY ISSUE B-56, " DIESEL GENERAT RELIABILITY" The Commission (with all Commissioners agreeing) has approved Option 4, as recommended by the staff.
In approving Option 4, the Commission would like to emphasize the following thoughts and concerns:
The importance of maintaining ac power, and consequently in
{
having reliable diesel generator performance, in assuring a low likelihood of core damage has consistently been shown in risk l
assessment studies.
l Since promulgation of the station blackout rule, the nuclear industry has made real progress in improving the reliability of diesel generators to start and run upon demand, and the current industry-wide average reliability, in excess of 98 percent, is quite satisfactory.
In balancing the recognition of these 3
efforts and the high level of actual diesel generator reliability achieved against the clear need to maintain such performance, the l
Commission believes a rule is not necessary.
Nevertheless, the Commission considers it imperative that this action not be misinterpreted as a signal that past efforts and vigilance can now be relaxed or possibly disbanded.
Hence, the industry should continue an aggressive program of maintenance as well as root cause analysis that will continue to offer assurance that diesel generator reliability will be maintained at a satisfactory level in the future.
SECY NOTE:
THIS SRM, SECY-93-044, AND THE VOTE SHEETS OF ALL COMMISSIONERS WILL BE MADE PUBLICLY AVAILABLE 10 WORKING DAYS FROM THE DATE OF THIS SRM 9304190164 930325 I O PDR 10CFR l
PT9.7 PDR
\\
l 1
~
t f
i i
l Finally, the staff and industry should focus on (1) evaluation methods and techniques that will permit rapid and early means of detecting significant degradation of diesel generator reliability, (2) examine diesel generator testing frequency and balance these with considerations of additional wear, and (3) explore the potential vulnerabilities of those applications where fewer than two safety-related power sources per unit, on average, are installed.
i i
i i
cc:
The Chairman l
Commissioner Rogers Commissioner Curtiss l
Commissioner Remick i
Commissioner de Planque OGC j
OIG Office Directors, Regions, ACRS, ACNW (via E-Mail) l OP, SDBU/CR, ASLBP (via FAX)
{
+
1 i
l l
. _. _