ML19209C072
| ML19209C072 | |
| Person / Time | |
|---|---|
| Site: | Fort Calhoun  |
| Issue date: | 09/18/1979 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML19209C069 | List: |
| References | |
| PR-790918, NUDOCS 7910110470 | |
| Download: ML19209C072 (7) | |
Text
Enclosure STAFFPOSITION s
l q
SAFE SiiUTDCWN CAPASILITY Staff Cencem Curing the staff's evahatien of fire protecticn pr: grams at c erating plants, one or mere specific plant areas may be identified
~
in which the staff dces not have adequate assurance that a pestulated fire will not damage both redundant divisions of shutd::wn systems.
This lack of assurance in safe shutdewn capability has resulted fr:m cne or both of the follcwing situatiens:
- Case A: The licensee has net adequately identified the syste=s and cc:;cnents required for safe shutdown and their location in specific fire areas.
Case 3: The licensee has not demenstrated that.he fire protecticn for specific plant areas wi'.1 prevent damage to both redundant divisiens of safe shutd:wn cc ;;cnents identified in these areas.
Fcr Case A, the staff has required that an adequate safe shutdewn analysis be performed. This evaluati:n includes the identifica:icn of the systems required for safe shutdewn and the 10:ati:n of the system c:::::nents in the plant.
- here it is determined by this evaluation.that safe shutd:wn c:=;cnents of both redundan divisiens are located in the same fire area, the licensee is required :: de:Onstrate that a ;cstulated fire will net damage both divisions er provide altamate shu:dewn capability as in Case B.
For Case 3, the staff may have required that an altamate shutdcwn capability be provided with is independent of the area cf c:ncern or the licensee may have prepcsed such a capability in lieu of certain additi nal fire protecticn :redifications in the area. The specific =cdificatiens asscciated with the area of c:ncern along with other systems and equipment already independent of the area form the altamate shutdewn capability. For each plant, the =cdifications needed and the c:mbinations of systems which provide the shutd:wn functions : ray be unique fcr each critical area; hcwever, the sh0 dewn functions provided shculd =aintain plant parameters within the beunds of the -limiting safety c nsecuences deemed ac:eptable f r the design basis event.
Staff ?:sition Safe shu:d wn ca: ability shculd be dem nstrated (Case A) er alte-na a snutd:wn ca: ability provided (Case 3) in ac::rdance with the guidelines previded bel:w:
- 1. Cesi:n ! asis Event S.e design basis event f:r ::nsidering *he.eed for alternate s n. ::wn i s a ;:s tul a a
' ire in a s:eci'i: f' re a&_a ::ntaining
-e:uncan: safe snu-d:.n':a:ies/ecui:ren-in :i:se pr:xi-ity anere i-as :een :e:e--i e :na: 'i e :r::e::i:n.ans cannet assure
- ..1 : sa's snu :>n :a:a:ilin.
Ti :e : reserve:.
T: :ases sncui:
te ::r.si:erec:
(i)
Offsite ;cwer is avaiia:1e; and (2) offsite
- >er is
- available.
. 79101109 76 1128 257
P00R ORC LL
~
~
- 2. Limitinc Safety Consecuences and Recuired Shutdcwn Functiens 2.1 No fissien product boundary integrity shall be affected:
a.
No fuel clad damage; b.
No rupture of any primar'y c clant bcundary; c.
No rupture of the containmnt.bcundary.
2.2 The reactor coolant system process variables shall be within these predicted for a less of ner=al ac pcwer.
2.3 The alternate shutdewn capability shall be able to achieve and maintain suberitical c:nditions in the ructor, maintain reactor c olant inventory, achieve and =aintain hot standby
- cenditiens (het shutdcwn' for a ENR) for an extended period of time, achieve cold shutdown
- c:nditiens within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> and maintain co'J shutdewn c:nditiens thereafter.
As defined in the Standard Technical Specifications.
- 3. Per ermance Geals e
1 The reactivity c:ntrol functicn shall be capable of adieving 3.1 and maintaining cold shutdtwn reactivity conditiens.
3.2 The reacter c:clant makeup functicn shall b'e capable of maintaining + reacter coplant level above the.t:p cf the core for SW s and in the pressuriter f:r P'4R's.
3.3 The reactor heat ra.=cval function shall be capable of achie,ving and =aintaining decay heat remeval.
3.4 The process menit ring function shall be capable of providing direct readings of the process variables necessary to perfora and c:ntrol the above functicas.
3.5 The suppcrting function shall be capable of providing t$e prect:ss c:oling, lubrication, et:. necessary to permit th.e cperatien cf the equi;mnt used fer safe shutdown by the systems identified in 3.1 - 3.4 3.5 The equi; ment and syste=s used to achieve and =aintain het standby c:nditiens (het shutdewn for a 5WR) shculd be (1) free af fire damage; (2) capable f maintaining such c nditiens for an extanded tire ;eried longer than 72 hcurs if the equipment -scuired to achieve and maintain cold shutdown is not available due to fire damage; and (3) capable of being pcwered by an ensite emergency power system.
3.7 The equi;=ent and systa=s used to achieve and =aintain c:1d shutdown condittens shculd be ef tner free Of fire dacage or the # ire damage t: sL:n tystems shculd :e limite s ud that re:ai s can be' a:e and ::ld shutd:wn c:nciti:ns acnieved witnin 72 hcurs.
Ecuipment anc syste=s usec cri:r :: 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> after the fire sneuid be ca:able of being ;cwered by an ensite emergency ;cwer syste=; these used after 72 curs may be pcwered by 1128 258
?)DDR~0RiNN1
-3 effsite power.
~
3.8 These systems need not be designed te (1) seismic category I criteria; (2) single failure criteria; er (3) cepe with other plant accidents such as pipe breaks er stuck valves (A;;endi: A STP 9.5-1), except these pertions of these systems which interface with er i= pact existing safe,y systems.
t
- 4. pWR Ecui:=ent Generally Necessary Fce Het Standby (1) Reactivity Centrol Reacter trip capability (scram). Scra:T:n capability e.g.,
charging pump, makeup pump cr high pressura injectica pu=c
~....
taking suction frc= concentrated berated water su; plies, and leticwn system if required.
(2) React:r C clan: Makeuc_
Reacter c clan: makeus ca: ability, e.g., charging pe=;s er the high pressure injection ;u=;s.
Pcwer Operated relief valves may be required to reduce pressure to allcw use of the high pressure injectica pu=;s.
(3) React:r C:clant System Pressure C:ntml Reac::r pressure control capability, e.g., charging pumps er pressuri:er heaters and use of the letdewn systa=s if required.
(4) Deca'v Heat Remeval Decay heat re=cval capability, e.g., ;cwer c:erated relief valves.(steam generatcr) er safety relief valves for heat removal with a water supply and eme gency er auxiliary feedwater pu=:s for :nakeup to the steam generator. Service water er other pu=;:s may be required to provide water for auxiliary feed pu=c sucticn if the cendensate s:Orage tank capacity is not adequate for 72 hcurs.
precess. enit:rine Inst u=entation (5)
M P-ocess :: nit: ring capability e.g., press.tri:er pressure and level, steam generat:r Tevel.
(5) Sue: ort.
~he ecui; rent required :: su:;;r: ::eration Of the above descri:ed snutd wn equi: rent e.g., c: :enen :: ling water servi:e wa ar, e:: and :nsi:e : wer scur:es ( AC, CC) wi:n
- neir ass:ciated ele: ri:a* cis ri:uti:n system.
1128 259
~
P00R ORGM
~
- 5. FWR Ecuiement Generally Necessary For Cold shutdow.*
(1) Reacter Coolant System pressure Reduction to Residual Heat Remeval System ( RnR) Caca:1st:y Reacter c:olant system pressure reductien by c:eldewn using steam generater power operated ntlief valves er atmespheric dump valves.
(2) Decay Heat Re eval Cecay heat remeval capability e.g., residual heat receval system, c:mponent cooling water system and service water system to removal heat and maintain cold shutdewn.
(3) Su: cert Support capability e.g., ensite pcwer scurces ( AC & CC) er offsite after 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> and the associr.ted electrical
~
distributica system to supply the abcve equi; ent.
Equipment necessary in additien to that already pr vided to maintain het s--
'y,
- 6. BWR Ecui: ment Generally Necessary For Het Shutdewn (1) Reactivity Centro 1_
Reactor trip capability (scram).
(2) Reacter C:elant Makeuo Reactor coolant inventory (makeup capability e.g., reacter core system RCIC) er the high pressure coolant isolatica c cling (HPCI).
injecticn system (3) Raarter pressure Centrol and Decay Heat Removal De:ressuri:atien system valves or safety relief valves for dump to the su;pressicn pool. The residual heat rencval system in steam c:ndensing mcde, and service water system may also be used for heat remeval to the ultimate heat sink.
(4) Sc::ressica Feel Cooline Residual heat remeval system (in su::ression ;cc1 c:oling c:ce) service water system t: maintain het shdtd:wn.
(5) Precess Menit rine
?r::ess :: nit: ring ca:a:ili y e.g., -sa:::r vessel level and :ressure and su::ressi:n :0:1 :e=eratur.
1128 260
PD0RORGIN1 m
(6) Su:: ort Support capability e.g., ensite pcwer s urce (AC & DC) and their associated distributien systems to pr vide for the shutdown equipment.
- 7. 5WR Ecui: ment Generally Necessarv Fer Cold Shutdewn*
At this point the equipment necessary for hot shutdewn has reduced the primary system pressure and temperature to where,the ER system may be placed in service in MiR cooling ::cde.
(1) Decay Heat Removal i
Residual heat re:: eval system in the MiR c:aling rede, service water system.
(2) Su: crt Onsite scurces (AC & CC) or offsite af ter 72 hcurs and their associated distributien systems to pr0 vide for shutdcwn equf; ment.
Equipment provided in additica to that for achieving het shutdewn.
- 8. Information Recuired Fer Staff Review (a)
Descriptien of the systems' or pcrtions thereof used to provide the shutdown capability and modifica icns required
,to achieve the alternate shutdewn capability if required.
(b) Syst'em design by drawings which shew normal and alternate
~
shutdewn centrol and pcwer circuits, locatien of components, and
. that wiring which is in the area and the wiring which is out of the area that required the alternate system.
(c)
Demonstrate that crianges to safety systems wiTT not degrade safety systa=s.
(e.g., new isolatien switches arid centrol switches shcuid meet cesign criteria and standards in FSAR for electrical equipment in the system that ce switch is is be installer; cabineu na: the switches are to be ecunted in shculd also meet the same criteria (FSAR) as ether safety related cabinets and
=aneis; :s avoid inadvertent isolatien fr m the ::nt ol
,:m, the isolatien switches should be keylocked, er alarmed ir, ce centrol reem if in the " local" er "is:1.a:ec" ;csiticn; periccic checks shculd be made :s verify switch is in the pre:er position f:r n:rmal c:erati:n; anc a single ransfer swit:n er c:ner new device should ne: be a scur:e for a single failure :: cause 1:ss f recundan safety systems).
[ iring, i.cluci.; =cwer s:;r:es f:r the
(:)
Cemenstrate tna:
c:ntr:1 cir:;i: and e: i: rent ::erati:n f:r ne ai arr.ata shut. wn.e:nCd. is incepenCen: Of e:ui: men: airi".g in the area :: :e avCided.
1128 261
- '---wee
i P00fDRGINAL (e)
Demonstrate that alternate shutd:wn pcwer scurces, including all breakers, have isolation devices en c:ntr:1 circuits that are routed through the area to be avoided, even if the breaker is to be cperated manually.
(f)
Demonstrate that if censee procedure (s) have been developed which describe the tasks to be parfcmed u effect the shutdcwn me thod. A sumary of these procedures should be submitted.
(.9)
Demonstrate that spare fuses are available'fer control cir:uits where these fuses,may be required in supplying pcwer to c:ntrol circuits used for the shutdewn method and may be blewn by the effects of a :able spreading roco fire. The spare fuses shculd be located c:nvenient to the existing fuses. The shutdown proce:ure shculd infern the cperator to check, these fuses.
(h)
Demonstrate that the manpcwer required to perfore the shutdown functiens using the precedures cf (f) as well as to provide fire brigade rembers to fight the fire is available as required by the fire brigade technical specifications.
(i) Demonstrate that adequate ac:eptance tests ars ar# r ned.
These shculd verify that: equip:ent operates frem the local centrol station when the transfer or is:tation switch is p1 aced in tne " local" ;;csitien and that t"e equiprent cannot be operated from the c:ntrol rec =; and that equip-ment operates frcm the centrol reem but cannet be cperated at the local c:ntrol station when the transfer er isciatien switch is in the " remote" positicn.
Technical Specificatiens of the surveillance requirements (j) and li=iting c:nditiens for operatien for that equipment not a'1 ready covered by existing Tech. Specs. Fcr example, if new isolati:n and centrol switches are added to a service water system, the existing Tech. Spec. surveillance require-ments en the service water system shculd add a statement similar to the follcwing:
"Every third pumo test should also verify that the pump starts frem tne alternate shutdewn statien after moving all service water system isciatien switches to the 1ccal centrol pcsitien."
(k) 0-mnstrate cat the systems available are ade:uate to ;erf:rm tne necessary shutdcwn functi:ns. The func:icns recuired sh uld be based On :revict.; analyses, if pcssible (e.g.,
in de FSAR), such as a 1:ss of nor.a1 a.c. :cwer er shutdcwn
- n a Gr:u: ! isolatien (3WR). De ecui: men: re:uired f:r the alternate ca:a:ility sh:uld be 'he same er scuivalent t:
- nat relied :n in ine ab ve analysis.
1128 262
e g
P00RORGM1 (1)
Demonstrate that repair procedures for cold shutdun systems are deveicoed and material for repairs is maintained en site.
O 4
e 0
4 N
e O
e e
y s
e 9
0 0
O 1128 263
..