ML19309B063
| ML19309B063 | |
| Person / Time | |
|---|---|
| Site: | Rancho Seco |
| Issue date: | 04/14/1978 |
| From: | Mattimoe J SACRAMENTO MUNICIPAL UTILITY DISTRICT |
| To: | Reid R Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8004020669 | |
| Download: ML19309B063 (3) | |
Text
.
C V
REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)
DISTRIBUTION FOR INCONING NATERIAL 50-312 R!!C: REID R tl ORG: NATTIMOE J J Dor.D ATE: 04/14/75 NRr
'3ACRAt1EP f0 MliN UTIl. DIST DATE RCVD: 04/19/78 DnCfYPE: 1.ETTER NOTARITED: NO COPIES PECEIVED SUOJECT-L TR 1 ENCL 0 FURNISHINO INFO RE A'3SURANCE THAT ::U9Jt CT FACILITY CAN CONTINUE TO OPERATE IN A SAFE N4t:NE R, IF A St1All RRFAK #7 THE FUI1P DISCHARCE SHOULD OCCUR Itt THE ECCS.
PLANT NAME: RANCHO SECO (SMUD)
REVIEWER INITIAI -
VJM DISTRIEUTOR INITIAL: 4
- u
- a.********** DISTRIBUTION OF THIS MATERIAL IS AS FOLLOWS ******************
GENERAL DISTRIBUTION FOR AFTER ISSUANCE OF OPERATING LICENSE.
(DISTRITMi ION CODL AOO1)
FOR ACTION:
OR r""'~
" 7 )
INTERNAL FILE **LTP ON!.Y(1)
NRC PDR**LTR ONI.Y( 1)
I &
t.
'm"Vr
OELD**LTR ONLY(1)
HANAUER**LTR ONLY(1)
CHECK **LTR ONLY(1)
EISENHUT**LTR ONLY(1)
SHAO**LTR ONLY(1)
BAER**LTR ONLY(1)
GUTLER**LTR ONLY(1)
EEB**L.TR ONLY ( 1 )
J COLLINS **LTR ONLY(1)
J.
MCOOUGHMLTR ONLY(1)
EXTERNAL IPDR'S SACRAMENTO. CA4aLTR ONLY(1)
REGION VrmLTR ONLY(1)
TIC **LTR ONLY(1)
NSIC**LTR ONLY(1)
ACRS CAT B**LTR ONLY(16)
DISTRIBUTION-
' TR 41 ENCL 0 CONTROL NER:
n r
.((E SIZE: 2P occo*******************************
THE END
- W 8004020 s
y J
SMUD
~
SACRAMENTO MUNICIPAL UTILITY DISTRICT O 6701 s street, Box 15830, sacramento, California 95813; (916) 452-3211 April 14,1978
...S v
9 7J Director of Nuclear Reactor Regulation
-r
~
Attention: Mr. Robert W. Reid, Chief
- n -
r%.1~
Operating Reactors, Branch 4 U. S. Nuclear Regulatory Comission
-a i-Eli Washington, D. C.
20555 B
N 5
w Docket No. 50-312
'3 Small Break Analysis Rancho Seco Nuclear Generating Station, Unit No.1
Dear Mr. Reid:
On April 12, 1978 B&W reported to the Commission that the "ECCS Analysis of B&W's 177 FA Lowered Loop NSS" (BAW 10103A, Revision 3, July 1977) did not include the worst case small break location.
In response to the concerns identified by Mr. Zwetzig, the District provides the following information which assures that the plant can continue to operate in a safe manner.
1.
In the unlikely event that a small break at the pump discharge should occur:
A.
Normally, both high pressure injection pumps will operate and adequate flow will be provided to ensure that all ECCS acceptance criteria are met and no operator action is required.
B.
If only one high pressure injection pump is immediately available, operator action is required.
The casualty procedures have been changed to require the operator to cross-connect the discharge of the operating high pressure injection pump to provide flow to each high pressure injection leg of both high pressure injection trains.
This operator action will be performed within 20 minutes and will ensure sufficient high pressure injection flow reaches the reactor vessel so that ECCS acceptance criteria are met up to a power level of 93%.
The District is currently limited to 75% power by failure of one of the main transformers.
The repair is not expected to be complete until sometime in August 1978.
l
-. M.
g AN ELECTRIC SYSTEM S E RVIN G MORE THAN 600,000 IN THE HEART OF C All F O R N I A
f
(%,
(
/
i Mr. Robert W. Reid April 14, 1978 2.
This change in casualty procedure will not have any adverse effect on any other postulated accidents or operating conditions.
Sincerely yours, M k.. A
' J.# J. Mattimoe Assistant General Manager and Chief Engineer cc:
Mr. R. H. Engelken NRC, Region V 1
4
't t-
,.~..
.