ML19309A665
| ML19309A665 | |
| Person / Time | |
|---|---|
| Site: | Rancho Seco |
| Issue date: | 05/03/1973 |
| From: | Davis E SACRAMENTO MUNICIPAL UTILITY DISTRICT |
| To: | Schwencer A US ATOMIC ENERGY COMMISSION (AEC) |
| References | |
| NUDOCS 8003310574 | |
| Download: ML19309A665 (3) | |
Text
-..-
AEC ~WPRIBUTIOil FOR PART 50 DOCXETA
~
TERIAL (TEMPORARY FORM)
CONTROL NO:
2959 FIIP N5 FRCd:
Sacramento Municipal DATE OF DOC:
DATE REC'D LTR MEMO RPr OTHER Utility District Sacramento, California 95813 E. K. Davis 5-3-73 5-7-73 x
TO:
A. Schwencer 1
39 SEE LOCAL PDR x _]
CIASS:
h0? IA70 INPUT NO CYS REC'D DOCKET NO:
40 50-312 DESCRIFfION:
' ENCLOSURES:
Ltr re our 3-7-73'Itr.... furnishing info regarding review of all safety related squigiment....trans the following:
Review of Control Circuits
,M$we?(([
(4O' cys rec'd)'
f*
PLANT NA?GS: Rancho Seco f,ffh, FOR ACTION /I.UORMATION 5-7-73 LB BUT".ER(L) nENCER(L)
ZIEMNN(L)
YOUNGBLOOD(E) y/4 U/ Copies W
Copies W/ Copies W/ Copies CLARK (L)
STOLZ(L)
ROUSE (FM)
REGAN(E)
U/ Copies W/ Copies W/ Copies' W/ Copies GOLLER(L)
VASSALTA(L)
DICKER (E)
W/ Copies W/ Copies N/ Copies W/ Copies KNIEL(L)
SCHE!:EL(L)
KNIGHTON(E)
W/ Copies W/ Copies W/ Copies W/ Copies InnduTAL DISTRIBUTION
(.-fEG 'FIIQ TECH REVIEW DENTON F&M WADE E
.m.u mn 6"HENDRIF/
GRIMES SMILhY BROWN E
sOGC, ROOM P-506A SCHROEDER GAMMILL NUSSBAUMER G. WILLIAMS E 4-MUNIZING/ STAFF
-fMCCARY KASTNER SHEPPARD E
&<XBE' sRTIGHT BALLARD LIC ASST.
GIAMBUSSO aPKWLICKI SPANGLER SERVICE L
A/T IND BOYD 40 WIIBON L
BRAITMAN V. MOORE-L(BWR) 6 STELIM ENVIRO A66ULBOURNE L SAL'IDIAN s-BEYOUNG-L(PWR)
M USTON MULLER SMITH L
SKOVHOLT-L NOVAK DICKER GEARIN L
PLANS P. COLLINS ROSS KNIGRTON DIGGS L
MCDONALD IPPOLITO YOUNGBLOOD TEETS L
DUBE REG OPR OfEDESCO REGAN LEE L
6 FIII & REGION (2) aJs0NG PROJ LEADER MAIGRET L
INFO MORRIS s EC7TAS SHAFER F&M C. MILES STm mOYA RAR m S ggygg_(y_gyg v0weR PMRMAI. DTSTHTPtJFTON
~
~
I
6 t'rI7fIE(ABERNATHY)
(1)(2)(9)-NATIONAL LAB'S PDR-SAN M
.MIC(BUCHANAN) l 1-R. CARROLL 'C, GT-B227 1-GERALD LELIDUCHE l-ASLB-YORE /SAYRE 1-R. CATLIN,E-256-GT' BROOKHAVEN NAT. LAB WOODWARD /HST.
1-CONSULTANf'S 1-AGMED(WALTER K0 ESTER, c.16 CYS ACES lEDDEEG sent 5-7-73 to NEWMARK/BLUfG/AGABIAN EM C. l+27, GT)
E. Goulbourne for Dis t.1-GERLAD ULRIKSON....ORNL l-RD...MUTIER...F-309G']
1 t' )
fib Oy."
SACRAMENTO MUNICIPAL UTILITY DISTRICT O 6201 S Street, Box 15830, Sacramento, California 95813; (916) 452 3211 May 3, 1973 Mr. Albert Schwencer, Chief
)
y Pressurized Water Reactors
/ q'y,. y ', Q
<hh Branch No. 4
/-
p
[(g h-j Directorate of Licensing
' TI I U. S. Atomic Energy Commission
- O G
,4 Washington, D. C.
20545 p
8/
7 Rancho Seco Nuclear Generating Station No. 1
/ f C/' 7 Docket No. 50-312 Review of Control Circuits N,,-
Dear Mr. Schwencer:
In your letter of March 7, 1973, you requested that the District perform a review of all safety related equipment at the plant to assure that disabling of one component does not, through incorporation in other interlocking or sequencing controls, render other components inoperable.
The District's review which included consideration of circuit breakers in the trip position, in the test position and in the racked out position has been completed. The findings of this review along with the proposed corrective action are contained in the attachment to this letter.
Your letter also requested that the District review pro-cedures to assure that whenever part of a redundant system is removed from service, the portion remaining in service is functionally tested immediately after the disabling of the affected portion and, if possible, before disabling of the affected portion.
The District will modify the appropriate sections of the technical specifications to state that prior to initiating mainten-ance on any safety related components, the duplicate (redundant) components shall be tested to assure operability with the component on which maintenance is being performed removed from service. The District believes that the surveillance requirements for all safety features equipment effectively constitute a prior test of redundant component operability.
Si st'e % ours, u
/
~
E. K.
avis General Manage'r
[
Attachment AN ELECTRlt SYSTEM SERV!NG MGRE THAN 600.000 IN THE HEART OF CAL 1F0RNia
STWTwl i l
O agg7 W8= k.l se uggggm A ;l.
REVIEW OF CONTROL CIRCUITS ma A review was made of the control circuits of all safety related equipment at the plant to assure that disabling of one component does not, through incorporation of interlocking or cequencing controls, render other components inoperable. The review included consideration of circuit breakers in the tripped position, in the test posirion and in the racked out position.
The results of this review are listed below:
?.. Control Circuits Interlocking Redundant Safety Features Equipment:
Make-up pump P-236 safety features actuation start circuit is inter-locked with 33b switch on HPI pump breaker. When HPI pump breaker is racked out, make-up pump is permitted to start. However, if 33b switch fails to close, make-up pump is prevented from starting. This failure does not affect operation of other HFi pump and therefore no corrective action is required. The technical specifications shall be revised to require that anytime the MU pump replaces a HPI pump, the SFA test signal be initiated to start the MU pump and operation of the pump and its fan cooler be verified.
2.
Control Circuits Interlockirg Safety Features Equipment of the Same Channel:
a.
Alterna'- 'upplies *or make-up pump lube oil pump are electrically interlos by 89,b auxiliary switches.
Failure of an 89/b switch to close a l prevent the lube oil pump from starting. With no safety features signal presect, loss of lube oil pressure will stop the makeup pump. However, wh,n a safety features actuation signal is present, the loss of lube oil pressure will not stop the makeup pump. Since the failure of the lube oil pump does not affect operation of the two HPI pumps and since this failure does not affect operation of the makeup pump during safety features actuation, no corrective action is required.
b.
Alternate supplies for emergency pump room air cooler that works in conjunction with the makeup pump are electrically interlocked by 89/b auxiliary switches. Failure of an 89/b switch to close will prevent the air cooler from starting. However, since during normal operation with outside power available, the pump room coolers are not needed and since the HPI pumps are redundant to the makeup pump no corrective action is required.
c.
The battery room exhaust fans are interlocked with the battery room j
supply fans.
If the battery room supply fan is removed or not in operation, the battery room exhaust fans are prevented from starting.
Since the battery room exhaust fans must run all the time to prevent dangerous accumulation of hydrogen in the battery rooms, the control circuit for the exhaust fans will be modified so that they will operate continuously regardless of whether the battery room supply fans are running or not.
In addition, annunciation of exhaust fan failure will be pro.ided in the concrol room,
\\
a r).'
d.
Air damper actuators are interlocked with the' emergency control room air conditioner.. If the breaker feeding the emergency control room air conditioner is removed, emergency air dampers cannot be. opened and normal air dampers cannot be closed. Since on detection of high radiation by R-15006, these dampers must operate, the control circuit for these dampers will be modified so that upon high radiation detection by R-15006 the emergency.
air dampers will automatically open and the normal Air damper will automatically close regardless of whether the emergency control room air conditioner U-545 is operable or not.
3.
No problems were noted on the rest of the control circuits reviewed.
4,
e e