ML20006C443
| ML20006C443 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 01/25/1990 |
| From: | Hukill H GENERAL PUBLIC UTILITIES CORP. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| C311-90-2006, NUDOCS 9002080046 | |
| Download: ML20006C443 (3) | |
Text
.
hy;,
e
- j 4-J GPU Nucloat Corporation:
Nuclear z,.om a;,-
Middletown, Pennsylvania 17067 0191 s
717 944 7621
' T'
-TELEX 84 2386 Wrlier's Direct Dial Number:
-f' January 25, 1990 C311-90-2006
[
' 7' U, S... Nuclear Regulatory Commission Attn: Document Control Desk Washington, 0;C.'20555 Gentlemen:
' \\
Three Mile Island _ Nuclear Generating Station, Unit 1 (TMI-1)
{
Operating' License NO. DPR-50 Docket No. 50-289 Respons'e To Station Blackout Rule.SER r
i
.By-letter dated April 17, 1989, GPU Nuclear submitted the TMI-1 response to the i
Station Blackout Hule (SBO). The NRC reviewed.the submittal and formally:
~
> responded to GPUN in the Safety Evaluation Report (SER) received on December:27, 1989.
In accordance with Rule requirements,-this~ letter transmits the results of our review of'the'SER. Various clarifications to specific items in the SER are-o"'
provided in the attachment.
- 1 As indic'ated in our submittal o'f 4/17/89; Modifications and associated Procedure changes' related to the TMI-1 SB0 Rule compliance are expected to-be
. completed by the.end-of refueling outage 9R.
Sincerely
+
H. D.
ukill 6r Vice President & Director, TMI-1 HDH/EP/lt
' Attachment-e L
"'cc:.R.'Hernan, USNRC l
W. ' Russell, USNRC, Region 1 i [8 L
J. Stolz,.USNRC 0
-F.. Young,-USNRC, TMI-1 l'
NUMARC' l
g l"
9002080046 900125 PDR ADOCK 05000289 P
PDC L
- y. ' r GPU Nuclear Corporation is a subsidiary of the General Public Utilities Corporation I
~
mm.
_-____,,m____
mp Oi h
n
('C.? e < s *
/
ATTACHMENT l' 4
/
E ll.
Clarification of Various issues Discussed in The TMI-1 SBO-SER 1.
General - In several sections in the SER the AAC Source is also referred.
i to as an EDG. The use of the term EDG does not imply that the AAC system and components are' required to meet Class 1E or Safety System requirements. Such requirements are not applicable to an AAC system and p
components.
2.
Pa.3, last paragraph, line 2:
u Issue - The SER states that the EDGs are continually pre-lubed and warmed.
Clarification - The TMI-1 EDGs are continually warmed. They are not-continually pre-lubed.
Pre-lubing is conducted prior to test starts.
3.
Pg.4, 2nd paragraph, line 3:
Issue - lhe SER refers to the independency of the AAC source'from TM1 services.
Clarification - Independency refers to TMI-2 services.
4 '.
pg.4, 2nd paragraph, line 6:
Issue - The SER refers to Figure 1.
Clarification - The SER did not include a Figure 1. It is assumed that the-figure referred to is identical to Attachment 1 (figure) of the 4/17/89 submittal, by GpuN in response to the SB0 rule.
- 5.
pg.4, 2nd paragraph, lines 8, 9 and 10:
Issue - The SER states that the DC power, independent of that used.for.
TMI-1, will be used to supply the AAC source and its associated breaker
- Control.
. Clarification The new DC source will provide power to the AAC source and lts associated breaker control, however it will not provide power for feeder breaker control on 4KV busses IC,1D, and 1E.
6.
pg. 4, last paragraph, lines 2 'and 3:
Issue - The SER states that undervoltage will automatically start the AAC supply.
Clarification - Undervoltage will no longer automatically start the AAC
. source.
The AAC source will be manually started from the TMI-1 control
- room, p,
v-f 3%y b
Clarification (Cont'd.) - The purpose of this change is to reduce operator burden associated with a Loss of Off-Site Power (not station blackout)
L o
U where allfor l' off the 2 TMI-1 EDGs start up, as well as the AAC EDG.
In n
this case the operator should focus his attention on loading the TMI-1 l
ll
- EDGs.
A started but unloaded AAC would divert operator attention to load the AAC 7
.~ generator as well.
Manually starting the AAC source from the control room still meets the SB0 E
rule requirements while reducing operator burden by not starting the AAC until the operator is ready to load it. This claritication was discussed with the NRC (R. Hernan). during a telephone call on December 29, 1989.
The NRC indicated this is acceptable and requested that this information be included in the contents of this letter.
7.
pg.6, 3rd paragraph, lines 3, 4 and 5:
1ssue - The SER states that the AAC EDG is required to have~a cooling system independent of off-site power, or TMI-1 power sources.
L Clarification - The AAC source will utilize, for cooling purposes, the TMI-1 fire service system.
Parts of this system have their own b'
independent power sources.
The fire service system can provide the necessary water for this cooling function during an SB0 without relying upon off-site power, the TMI-1 EDGs or the TMI-2 DC distribution system.
8.
Pg.7, last paragraph, last sentence:
Issue - The SER states a contingency based on the control room being cooled by the HVAC system (s) powered by the AAC Source Clarification - The control' room HVAC is powered from either TMI-1 emergency bus. The AAC source will'be available within 10 minutes to power either emergency bus:and its associated equipment. The AAC source
' has the. capacity and capability of the normal EDGs and therefore can power the: control room HVAC loads.
- 9.
pg.9, last paragraph:
Issue-- The SER states that the modifications are scheduled for the Fall of 1991.
Clarification - These modifications will be performed during refueling outage 9R (which is currently scheduled for the Fall of 1991).
10.
pg.10, 2nd paragraph, last sentence:
Issue'- The SER states that the independence of TMI-1 power sources for the AAC source cooling water and other equipment is subject to review by the NRC.
Clarification - See Clarification #7 above.
4 i
-