ML20046B593

Proposed Tech Specs 3.8.2,3.8.5,3.8.8 & 3.8.10 & Associated Bases Re Electrical Power Sys

ML20046B593
Person / Time
Site:	05200001
Issue date:	07/21/1993
From:	GENERAL ELECTRIC CO.
To:
Shared Package
ML20046B592	List: ML20046B591 ML20046B593
References
NUDOCS 9308050200
Download: ML20046B593 (30)

Text

e-AC Sources-Shutdown l

3.8.2 3.8 ELECTRICAL POWER SYSTEMS 3.8.2 AC Sources-Shutdown LCO 3.8.2 The following AC electrical power sources shall be OPERABLE:

One qualified circuit between the offsite transmission a.

network and the onsite Class 1E AC electrical power distribution subsystem (s) required by LCO 3.8.10,

" Distribution Systems-Shutdown"; and g 4, g I

b.

One diesel generator (DG) capable of supplying one division of the Bi"irir i n 2 onsite Class 1E AC electrical power distribution subsystem (s) required by LCO 3.8.1 @

Une rualified circuit between the offsite transmission c.

and th ision 3 onsite Class rical power distrioution tem o an the circuit in LCO 3.8.2.a. or

~

n 3 OG when the Division 3 onsite AC electrica distribution

/

sub ' sem is required by LCO 3.8.10.

_/

"'N O hr /8"#/'" Nd MODE $.4-e*1f5 APPLICABILITY:

During movemeNof irradiated fuel assemblies in the) //rd ree

[p+1 y & secondary containment.

freoure v'e n e /

00"]O)

At%7R OWR /'r STS 3.8-19 R=.

O, 00/23/0F 9308050200 930721

[

PDR ADOCK 05200001 9 PDR lL; A

j i

LCO 3.8.2-AC SOURCES-SHUTDOWN j

(A d 2ed)

CONDITION REOUIRED ACTION COMPLETION TIME

'l I

A. Required offsite AC A.1 Operate the CTG and immediately circuit inoperable, align it to the required AC bus (es).

j 98 A_NR i

Required DG inoperable.

i A.2 initiate action to immediately restore required offsite circuit or required DG to OPERABLE status.

i f

I i

i i

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I i

i 1

i AC Sources-Shutdown 3.8.2 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME

$ 4 - Or.

or ::rc ic w ieu

---

NOTE-------------

offsite ci.-uin Enter applicable Condition 4"^^"^1a and Required Actions of y ggy ye ut es tC0 3.8.10. with one required division de-energized as a nu 567 A C-result of Condition A.

gg7g gj u g f /,6 ( T d;, a 1

Declare affected 6

required feature (s)

Imediately r;pd o pg yd-//n with no offsite power

/

available inoperable.

e., c/ C o n n et d

u Vf'l fo gg yd M2.1 Suspend CORE A'd

/u)(6),

ALTERATIONS.

Imediately AND f2.2 Suspend movement of irradiated fuel Imediately assemblies in the

[ primary and secondary]

containment.

-_ND A

g 4.2.3 Initiate action to suspend operations Imediately with a potential for draining the reactor vessel (OPDRVs).

AND 4.2.4 Initiate action to restore required Imediately offsite power circuit i

to OPERABLE status.

(continued)

BWR/6 STS 3.8-20 Rev.

O, 09/28/92

AC Sources--Shutdown 3.8.2 ~

ACTIONS (dtntinued)

COND1{l0N REQUIRED ACTION GdMPLETIONTIME f

j B.

Division 1 or B.1 Suspend CORE Immediately required DG ALTERATIONS.

inoperable.

EME B.2 Suspend m ement of Immediately irradia d fuel assem ies in

[pr' ary ]and s ondary ntairment.

3 l

6ED l 'tiate action to Immediately sus end OPDRVs.

l AND B.4 Initiate ction to Immediately restore re utred DG to OPERABLE tatus, i

C.

Requ' ed Division 3 DG C.1 Declare HPCS [and C

[72 hours]

~

in erable.

Standby Service Wat System) inoperable.

N s

4 I

)

BWR/6 STS 3.8-21 Rev.

O, 09/28/92 1

i

AC Sources--Shutdown 3.8.2 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.8.2.1

---

NOTE--------------------

The following SRs are not required to be

erfo rmed:

SR 3.8.1.3, SR 3.8.1.8 through SR 3.8.1.11, SR 3.8.1.13 throogh SR3.8.1.16,[SR3.8.1.18),and SR 3.8.1.19.

For AC sources required to be OPERABLE, the In accordance SRs of Specification 3.8.1, except with applicable SR 3.8.1.17 and SR 3.8.1.20, are SRs applicable.

t I

3.8-22 Rev.

O, 09/28/92 SWR /6 STS

AC Sources-Shutdown B 3.8.2 B 3.8 ELECTRICAL POWER SYSTEMS B 3.8.2 AC Sources-Shutdown BASES BACKGROUND A description of the AC sources is provided in the Br.ses for LCO 3.8.1, "AC Sources-Operating."

APPLICABLE The OPERABILITY of the minimum AC sources during M00E/-4-<- /

SAFETY ANALYSES --an&5, ensures that:

a.

The unit can be maintained ir the shutdown or i

refueling condition for extended periods; b.

Sufficient instrumentation and centrol capability is available for monitoring and maintaining the unit status; and Adequate AC electrical power is provided to mitigate c.

events postulated during shutdown, such as an f,,3,/g decq

% Sert:r.: drei-de 7. ;f th: :: eh or a fuel handling h ed rdmoV2l 7

accident.

In general, when the unit is shut down the Technical Specifications (TS) requirements ensure that the unit has the capability to mitigate the consequences of postulated i

accidents. However, assuming a single failure and concurrent loss of all offsite or loss of all onsite. power is not required. The rationale for this is based on the fact that many Design Basis Accidents (DSAs), which are analyzed in MODES 1, 2, and 3. have no specific analyses in MODES 4 and 5.

Worst case bounding events are deemed not credible in MODES 4 and 5 because the energy contained within the reactor pressure boundary, reactor coolant temperature and pressure, and the corresponding stresses result in the probabilities of occurrence significantly reduced or eliminated, and minimal consequences. These deviations from DBA analysis assumptions and design requirements during shutdown conditions are allowed by the LCO fer required systems.

During MODES 1, 2, and 3 various deviations from the analysis assumptions and design requirements are allowed within the ACTIONS. This allowance is in recognition that (continued)

BWR/6 STS B 3.8-35 Rev. O,09/28/92

>n

._,_,.r

1 AC Sources-Shutdown B 3.8.2 i

~

)

BASES APPLICABLE certain testing and maintenance activities must be conducted SAFETY ANALYSES provided an acceptable level of risk is not exceeded.

(continued)

During MODES 4 and 5, performance of a significant number of I

required testing and maintenance activities is also required. In MODES 4 and.5, the activities are generally planned and administratively controlled. Relaxations from typical MODE 1 2, and 3 LCO requirements are acceptable i

during shutdown % DES based on:

a.

The fact that time in an outage is limited. This is a risk prudent goal as well as utility economic consideration.

b.

Requiring appropriate compensatory measures for certain conditions. These may include administrative controls, reliance on systems that do not necessarily meet typical design requirements applied to systems credited in operating MODE analyses, or both.

c.

Prudent utility consideration of the risk associated with multiple activities that could affect multiple systems.

I ractical, the ability to Maintaining, to the extent p(even if not meeting d.

perfore required functions MODE 1, 2, and 3 OPERASILITY requirements) with systems assumed to function during an event.

In the event of an accident during shutdown, this LC0 ensures the capability of supporting systems necessary to avoid immediate difficulty, assuming either a loss of all offsite power or a loss of all onsite (diesel generator I

(06)) power.

The AC sources satisfy Criterion 3 of the NRC Policy Statement.

LCO One offsite circuit capable of supplying onsite Class 1E '

t power distribution subsystem (s) of LC0 3.8.10, ' Distribution Systems-Shutdown," ensures that all required HvtsmprT loads, ?ht'= l hd. r hth, are powered from offsite power. An OPERA 8LE DG, associated with a Division 1 er s, e A 3 Hv+e4e*4 Distribution System Engineered Safety Fea,ture (ESF) bus required OPERABLE by LC0 3.8.10, ensures a diverse

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(continued)

BWR/6 STS B 3.6-36 Rev.

O, 09/28/92

AC Seurces-Shutdown f.,

8 3.8.2 l

BASES i

LCO power source is available to provide electrical power f-(continued) support, assuming a loss of the offsite circuit.

!'-M ia v, k.'

a--

t'

' ! ;5 p r n ;.; r; = = :; n y (55 ) ' - ---~ i --e

+ a C ; a,. sepsi.6 oiisiis si. suis ie th; a'

ir e-2 i

Chn :..... L isu..sel p...- dutrit + 4 aa -d ;,;;;;, er-

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g s ne

,, nornie e ne..

,4..

_.;r f;r th; "M S.

Together, OPERABILITY of the required offsite circuit and DG ensure the availability of sufficient AC sources to operate the plant in a safe manner and to i

mitigate the consequences of postulated events during

-l shutdown (e.g., fuel handling accidents, n u t; m ; d b ed U

/oss de e.)y L.

d-af d: ).

Ye ns Vd/

The qualified offsite circuit (s) must be capable of maintaining rated frequency)and voltage while connected to l

their respective ESF bus (es, and accepting required loads Qualified offaite circuits are those during an accident.

that are described in theWSAR and are part of the licensing basis for the plant. 05: cff-f;; cf...;i c;=fet: M

.;ic,;,.. 6..;.4 di: r-eet te

• 'a er;rtf= n 're

'teac;f;.xn !! rf 21, the !! ;; M =-"'re tr;=fr-~_,

t'e ESF t = :f:.x n !! rf ?!. -' *ka - :; rt! = :irnit

-p th...J uviny i..;er t r o n t: :" t.M : " CT t==

r;;;i r; ty '.00 2.".!".]

The required 06 must be capable of starting, accelerating to rated speed and voltage, and connecting to its respective ESF bus on detection of bus undervoltage, and accepting required loads. This sequence must be accomplished within 7 8-* 9 6 seconds. Each DG aust also be capable of accepting required loads within the assumed loading sequence intervals, and sust continue to operate until offsite power can be restored to the ESF buses..These capabilities are required to be set from a variety of initial _ conditions such DG in standby with the engine hot, DG in standby with as:

the engine at ambient conditions, and DG operating in-parallel test mode.

1 l

Proper sequencing of loads, including tripping of nonessential loads, is a required function for DG

_i

_ [!_ r_lfitir,c f: Q ;g..g g;{.fr..

a-0PERASILITY.

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... n,

.. m,

-.----....i.......-

...y -.i

".....in.....

$ de r;Q;!NI k

4rntain]yiswd...y l

(continued) 3 3.8 37 Rev. O,09/28/92 BWR/6 STS

q AC Sources-Shutdown

+.

p.

Addown cordle", M is 8 3.8.2 a cc y vabl*

N*Y e

BASES N

LCO It is eteeptiM : Sr divisi;n; : S ere tf e 6 -in-(continued)

-thet 5 a ~diti:::, grit" ga single offsite i

circuit to supply all required divisiont. - $; '.powe

,; ;7;;; 5 gjjj { tp h r: pi--I 'e c ":it: ;ir;.;;; o yfgg ;,, g

........y As described in Applicable Safety Analyser, in the event of I

an accident during shutdown, the TS. are designed to maintain the plar.t in a condition such that, even with a single failure, the plant will not be in inmediate difficulty.

The AC sources required to be OPERA 8LE in MO i L APPLICABILITY during movement of irradiated fuel assemblies in i

94l mph-y er secondaryVcontainment provide assurance that-R'N aahef deca heat remodal 1

Systems to provide if- ;.;.y ; : n hat in w,,;; g -- he; d

l geli.]

t a.

AePC are ava,ilable for the irrad,iated fu,el in the core >4*-

c.avdj $gedey gi m

..,_ a..

a..

2-m_

.s..

gp4

' M ; 7 5 # [ E T; [ E M, E.'E'I' W6 j

b.

Systems needed to mitigate a fuel handling accident NA" g (t M M (t* d p

are available; d!

c.

Systems necessary to mitigate the effects of events le 55 s

that can lead to core damage during shutdown are i

available; and i

d.

Instrumentation and control capability is available for monitoring and maintaining the unit in a cold I

shutdown condition or refueling condition.

1 The AC power re uirements for MODES 1, 2

.are covered g g gp e3 a., d fi 'wi n e286 l

in LCO 3.8.1) an r

e aaker \\ese t in %e ve{uet;4 I

r g

cavi&3 4 23 ft AboVC Md '

i

- gT!M g

yesdorfrebuVf'V6he1-fl**]e, fI t <.o 3. 8.Y, -

j p.,ereya An offsite circuit is considered inoperable if it is not 1

available to one required ESF division. If two or more 1

k

(,,1 _

E16ett-kV buses are required per LC0 3.8.10 division (s) nedffej8-wtth offsite power available may be capable of supporting sufficient required features to allow continuation of CORE ALTERATIONS, fuel movement, and operations with a potential (continued).

8WR/6 STS

_8 3.8-38 Rev. 0,09/28/92 i

l

~

LCO 3.8.2 Bases (Y16 d )

f

' Insert 2:

ACTIONS A.1 and A.2 3

The onsite combustion turbine generator (CTG) can be started and aligned to supply AC power to one or two ESF divisions. Connecting the CTG to the required buses as required by Required Action A.1 compensates for the inoperability of either the offsite power line or the DG. Action is required to be initiated immediately to restore one required offsite power circuit or one required DG to OPERABLE status and to continue this action until the LCO requirements are restored in order to provide the necessary AC power to the plant safety systems.

b i

9 1

i i

I a

i l

m...__,

AC Sources-Shutdown B 3.8.2 BASES 0,#.1 (continued)

ACTIONS for draining the reactor vessel. By the allowance of the option to declare required features inoperable with no offsite power available, appropriate restrictions can be implemented in accordance with the affected required feature (s) LCOs' ACTIONS.

6 6

6 ll 0

.2.1. (2.2. X.2.3. #2.4. S. L 0.2. 0.3. end C..W.

With the offsite circuit not available to all required divisions, the option still exists to declare all required features inoperable. Since this option may involve undesired administrative efforts, the allowance for sufficiently conservative actions is made. With the-required I hpenNe, the minimum required diversity of AC s

j ; 4 le 9 0 3 V1 power sources is not available. It is, therefore, required d red A C-to suspend CORE ALTERATIONS, movement of irradiated fuel Y# b Ofgg/)6L6 assemblies in the [ primary or secondary containment], and pwae3 activities that could potentially result in inadvertent a-d Se cf6 draining of the reactor vessel.

g.9 Suspension of these activities shall not preclude completion

/9 aef Y s

g2r of actions to establish a safe conservative condition.

These actions minimize probability of the occurrence of ho '/ u[/'

postulated events.

It is further required to initiate to N 8 y o ut action imediately to restore the required AC sources and to p

continue this action until restoration is accomplished in p jn)J order to provide the necessary AC power to the plant safety AG i

systems.

Notwithstanding performance of the above conservative Required Actions, the plant is still without sufficient AC power sources to operate in a safe manner. Therefore, action must be initiated to restore the minimum required AC power sources and continue until the LCO requirements are restored.

The Completion Time of imediately is consistent with the required times for actions requiring prompt attention. The restoration of the required AC electrical power sources should be compir < d as quickly as possible in order to minimize the ti.

during which the plant safety systems may be without suffi_ 2nt power.

(continued)

BWR/6 STS B 3.8-39 Rev.

O, 09/28/92

i

~

AC Sources-Shutdown

. l B 3.8.2 BASES 6

8 6

6 ACTIONS E.2.1. 4.2.2. (.2.3. (.2.4. 4.1. B.2. B.2. r.d 0.,4 (continued)

Oo Pursuant to LCO 3.0.6, the' Distribution System ACTIONS are l

not entered even if al AC ources to it are inoperable, resultinginde.ener'atio(n. Therefore, the Required

{

Actions of Condition have bee modified by a Note to indicate that when Co ition A s entered with no AC power.

to one ESF bus, ACTIONS for L 0 3.8.1 must b imediately entered. This Note allows Condition A o provi e 6

requirements for the loss of the offs te circuit whether or not a division is de-energized. LC0 3.8.10 provides the 9

appropriate restrictions for the situation involving a-de-energized division.

t l

When t CS is required to be OPERABLE, and the

- ision 3 t

DG is inoper the required diversity of ower sources to the HPCS is no allable. Since th ources only.

affect the HPCS, the S is decla noperable and the l

Required Actions of the ect rgency Core Cooling Systems LCO entered.

In the event all s es of power Division 3 are lost, Condition A wi iso be entered a ret that the ACfIONS of LC0 3.8.

taken. If only the Div' 3 DG is inoper

, and power is still supplied to H 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> is all to restore the DG to OPERA 8LE. This is re ble l

nsidering HPCS will still perfom its function, absen additional single failure.

SURVEILLANCE SR 3.8.2.1-REQUIREMENTS SR 3.8.2.1 requires the SRs from LC0 3.8.1 that are necessary for ensuring the OPERASILITY of the AC sources in other than MODES 1, 2, and 3.

SR 3.8.1.17 is not required to be met because the required OPERASLE OG(s) is not required to undergo periods of being syn.chronized to the offsite circuit. SR 3.8.1.20 is excepted because starting =

independence is not required with the OG(s) that is not-required to be OPERA 8LE. Refer to the corresponding Bases for LC0 3.8.1 for a discussion of each SR.

1 (continued) gynyym;g 8 3.8 40 Rev.

0, 09/28/92

=

w e,

y

~

AC Sources--Shutdown I

/ :

B 3.8.2 BASES SURVEILLANCE SR 3.8.2.1 (continued)

REQUIREMENTS This SR is modified by a Note. The reason for the Note is to preclude requiring the OPERABLE DG(s) froc being paralleled with the offsite power network or otherwise rendered inoperable during the performance of SRs. With limited AC sources available, a single event could compromise both the required circuit and the DG.

It is the intent that these SRs must still be capable of being met, but actual performance is not required during periods when the DG is required to be OPERABLE.

i REFERENCES

'4,

i 1

I i

l 8 3.8-41 Rev.

O, 09/28/92

;/; ;;;

ad defaal

~

DC Sources-Shutdown A 3.8.5 3.8 ELECTRICAL POWER SYSTEMS a n d de [ u e h +iy 3.8.5 DC Sources-Shutdowng LCO 3.8.5 DC electrical power subsystem (s) shall be OPERABLE to th supportg e electrical power distribution subsystem (s) required by LC0 3.8.10, " Distribution Systems-Shutdown."

ved ofEKAOLffenbreS Q*4d ye APPLICABILITY

MODES 4 and 5, During movement of irradiated fuel assemblies in the tpri=ry cr secondary containment.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.

One or more required A.1 Declare affected Immediately DC electrical power required feature (s) subsystems inoperable.

inoperable

[

/

A.2.1 Suspend CORE Immediately

/

ALTERATIONS.

/

b#

( d.t g i m l~' " }e A &

AND ygd Org F8 A.2.2 Suspend movement of Immediately

+

4c> FO cul8 #

irradiated fuel 9 C 6/g [r,'c3I assemblies in the jo

[ primary or l

4 secondary]

hu[9[f fed Jh [d).

containment.

AND i

A.2.3 Initiate action to Immediately suspend operations with a potential for i

draining the reactor vessel.

AND (cortinued)

BWR/6 STS 3.8-30 Rev.

O, 09/28/92 1

fb DC Sources--Shutdown 3.8.5 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME I

l A.

(continued)

A.2.4 Initiate action to Immediately restore required DC i

electrical power subsystems to OPERABLE status.

1 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.8.5.1

---

NOTE-------------------

The following SRs are not required to be performed: SR 3.8.4.6, SR 3.8.4.7, and l

SR 3.8.4.8.

l I

for DC sources required to be OPERABLE the In accordance following SRs are applicable:

with applicable SRs SR 3.8.4.1 SR 3.8.4.4 SR 3.8.4.7 SR 3.8.4.2 SR 3.8.4.5 SR 3.8.4.8.

SR 3.8.4.3 SR 3.8.4.6 i

BWR/6 STS 3.8-31 Rev.

O, 09/28/92 1

__________________-________________________________J

l q., d Acf e DC Sources-Shutdowh f

8 3.8.5 8 3.8 ELECTRICAL POWER SYSTEMS I<efuelig (f

B 3.8.5 DC Sources-Shutdown And 3

BASES BACKGROUND A description of the DC sources is provided in the Bases for LCO 3.8.4, "DC Sources-Operating."

i APPLICABLE The initial conditions of Design Basis Acc_ijent and SAFETY ANALYSES transient an lyses in theS$AR, ChapterM67 (Ref.1) and Chapterli (Ref. 2), assume that Engineered Safety Feature l

systems are OPERABLE.

The DC electrical power system provides normal and emergency DC electrical power for the diesel generators, emergency auxiliaries, and control and switching during all MODES of operation.

The OPERABILITY of the DC subsystems is consistent with t'he 1

initial assumptions of the accident analyses and the requirements for the supported systems' OPERABILITY.

The OPERABILITY of the minimum DC electrical power sources during MODES 4 and 5 ensures that:

a.

The facility can be maintained in the shutdown or refueling condition for extended periods; b.

Sufficient instrumentation and control capability is available for monitoring and maintaining the unit status; and i

c.

Adequate DC electrical power is provided to mitigate

)

events postulated during shutdown, such as an inadvertent draindown of the vessel or a fuel handling j

accident.

The DC sources satisfy Criterion 3 of the NRC Policy j

Statement.

~

• {4 wet battery M,gr subsystems, each consisting of ' tone The DC electrical po LCO g

A study A,

the corresponding control equipment and interconnecting omA w. Vf W h I cabling within the division, are required to be OPERA 8LE to

$ms W W P *,

J (

f (continued) qwRfe-395 8 3.8-60 Rev. 0,09/28/92

)

1

~ I

M DC Sources-Shutdown B 3.8.5 BASES l

LCO support required divisions of Distribution System divisions (continued) required OPERABLE by LCO 3.8.10. " Distribution Systems-Ope rati ng. " This ensures the availability of sufficient DC electrical power sources to operate the unit in a safe manner and to mitigate the consequences of postulated events during shutdown (e.g., fuel handling accidents and inadvertent reactor vessel draindown).

APPLICABILITY The DC electrical power sources required to be OPERABLE in MODES 4 and 5 and during movement of irradiated fue[lpro assemblies in the'(pW:ry cr-secondary containment assurance that:

a.

Required features to provide adequate coolant inventory makeup are available for the irradiated fuel assemblies in the core in case of an inadvertent draindown of the reactor vessel; b.

Required features needed to mitigate a fuel handling accident are available; c.

Required features necessary to mitigate the effects of events that can lead to core damage during shutdown are available; and d.

Instrumentation and control capability is available for monitoring and maintaining the unit in a cold shutdown condition or refueling condition.

The DC electrical power requirements for MODES 1, 2, and 3 are covered in LCO 3.8.4.

ACTIONS A.I. A.2.1. A.2.2. A.2.3. and A.2.4 tape ge au S 6 74f more than one DC distribution subsystem is required according to LCO 3.8.10, the DC subsystems remaining OPERABLE with one or more DC power sources inoperable may be capable of supporting sufficient required features to allow continuation of CORE ALTERATIONS, fuel movement, and i

operations with a potential for draining the reactor vessel.

By allowing the option to declare required features inoperable with associated DC power source (s) inoperable, (continued)

Oua/; 25' B 3.8-61 Rev.

O, 09/28/92

4 DC Sources-Shutdown i

B 3.8.5 BASES ACTIONS A.I. A.2.1. A.2.2. A.2.3. and A.2.4 (continued) appropriate restrictions are imple ed in accordance with n

the affected system LCOs' ACTIONS.

In many instances this option may involve undesired administrative efforts.

Therefore, the allowance for sufficiently conservative actions is made (i.e., to suspend CORE ALTERATIONS, movement (v w

S of irradiated fuel assemblies, and any activities that c result in inadvertent draining of the reactnr vessel).

9N Suspension of these activities shall not preclude completion of actions to establish a safe conservative condition.

These actions minimize the probability of the occurrence _of postulated events. fit is further requireo to immediately (initiateactiontorestoretherequiredDCelectricalpowe]r f subsystems and to continue this action until restoratio accomplished in order to provide the necessary DC electrical power to the plant safety systems.

Notwithstanding perforinance of the above conservative Required Actions, the unit is still without sufficient DC power sources to operate in a safe manner. Therefore, action must be initiated to restore the minimum required DC power sources and continue until the LCO requirements are restored.

The Completion Time of immediately is consistent with the required times for actions requiring prompt attention. The restoration of the required DC electrical power subsystems a

should be completed as quickly as possible in order to i

sinimize the time during which the plant safety systems may be without sufficient power.

i SURVEILLANCE SR 3.8.5.1 REQUIREMENTS N6 '" # * *",

FSR 3.8.5.1 requires performance of all Surveillances required by SR 3.8.4.1 through SR 3.8.4.8.

Therefore, see oc. m c m e. w N SA

) the corresponding Bases for LCO 3.8.4 for a discussion of each SR.

sus syseer is Raou s r,

ss np ER+S LE,

i REFERENCES 1.

stSAR,Chapterh6[

A W it.2. S/SAR, Chaptek15[

i 5 0/5 STS _

B 3.8-62 Rev.

0, 09/28/92

I-I Inverters -Shutdown 3 3.8.8 A d ff ue/I")

3.8 ELECTRICAL POWER SYSTEMS ad/d[4eN"J 3.8.8 Inverters-Shutdown O

MM

$ -fu h$e 3

and LCO 3.8.8 Inverter (s) shall be OPERABLE to support)the onsite Class 1E AC vital bus electrical power distribution subsystem (s) required by LCO 3.8.10, " Distribution Systems-Shutdown."

P APPLICABILITY:

H0 DES 4 and 5, Duringa ovement of irradiated fuel assemblies in the m - -" ^* secondary containment.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME required (

A.1 Declare affected Imediately A.

One or mor inverters inoperable.

required feature (s) inoperable and y

inrWde aeFien lo OR restore reguMd G~Shlus.

verf er.s o opeyrACL en A.2.1 Suspend CORE Imediately ALTERATIONS.

AND A.2.2 Suspend handling of Imediately irradiated fuel assemblies in the

[ primary or secondary]

containment.

AND A.2.3 Initiate action to Imediately suspend operations with a potential for draining the reactor vessel.

AND (continued)

BWR/6 STS 3.8-38 Rev.

O, 09/28/92 t

Inverters--Shutdown 3.8.8 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.

(continued)

A.2.4 Initiate action to immediately restore required inverters to OPERABLE status.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.8.8.1 Verify correct inverter voltage 7 days

[ frequency,] and alignments to [ required]

AC vital buses.

BWR/6 STS 3.8-39 Rev.

O, 09/28/92

Inverters-Shutdown B 3.8.8 8 3.8 ELECTRICAL POWER SYSTEMS B 3.8.8 Inverters-Shutdown BASES BACKGROUND A description of the inverters is provided in the Bases for LCO 3.8.7, " Inverters-Operating."

APPLICABLE TheinitialconditionsofDesignBasisAccident(T67 DBA) and SAFETY ANALYSES transient accident analys Je in theS/SAR, Chapter (Ref.1) and Chapterd15f' (Ref. 2), assume Engineered Safety Feature systems are OPERABLE. The DC to AC inverters are designed to provide the required capacity, capability, redundancy, and reliability to ensure the availability of necessary power to the Reactor Protection System and Emergency Core Cooling Systems instrumentation and controls so that the fuel, Reactor Coolant System, and containment design limits are not exceeded.

The OPERABILITY of the inverters is consistent with the initial assumptions of the accident analyses and the requirements for the supported systems' OPERABILITY.

The OPERABILITY of the minimum inverters to each AC vital bus during MODES 4 and S ensures that:

a.

The facility can be maintained in the shutdown or refueling condition for extended periods; b.

Sufficient instrumentation and control capability are available for monitoring and maintaining the unit status; and c.

Adequate power is available to mitigate events postulated during shutdown, such as an inadvertent draindown of the vessel or a fuel handling accident.

The inverters were previously identified as part of the Distribution System and, as such, satisfy Criterion 3 of the NRC Policy Statement.

(continued)

- NR/C STs B 3.8-75 Rev.

O, 09/28/92 49 wi' 75

O Inverters-Shutdown B 3.8.3 BASES (continued)

LCO The inverters ensure the availability of electrical power for the instrumentation for systems required to shut down the reactor and maintain it in a safe condition after an anticipated operational occurrence or postulated DBA.

The battery powered inverters provide uninterruptible supply of AC electrical power to the AC vital buses even if the f,9 t.,t15 kV safety buses are de-energized. OPERABLE inverters require the AC vital bus be powered by the inverter througn inverted DC voltage.

This ensures the availability of sufficient inverter power sources to operate the plant in a safe manner and to mitigate the consequences of postulated events during shutdown (e.g., fuel handlir.g accidents and inadvertent reactor vessel draindown).

APPLICABILITY The inverters required to be OPERABLE in MODES 4 and 5 and also any time during movement of irradiated fuel assemblies in the% primary or secondaryfcontainment provide assurance that:

a.

Systems to provide adequate coolant inventory makeup are available for the irradiated fuel in the core in case of an inadvertent draindown of the reactor vessel; b.

Systems needed to mitigate a fuel handling accident are available; c.

Systems necessary to mitigate the effects of events that can lead to core damage during shutdown are available; and d.

Instrumentation and control capability is auilable for monitoring and maintaining the unit in a cold shutdown condition or refueling condition.

Inverter requirements for MODES 1, 2, and 3 are covered in LCO 3.8.7.

ACTIONS-A.I. A.2.1. A.2.2. A.2.3. and A.2.4 If two divisions are required by LCO 3.8.10, " Distribution Systems-Shutdown,' the remaining OPERABLE inverters may be (continued) em 45 8 3.8-76 Rev.

O, 09/28/92

-'4 Inverters-Shutdc.n B 3.8.8 BASES 3

l ACTIONS A l. A.2.1. A.2,2. A.2.3. and A.2.4 (continued) capable of supporting sufficient required feature (s) to allow continuation of CORE ALTERATIONS, fuel movement, and operations with a potential for draining the reactor vessel.

By the allowance of the option to declare required feature (s) inoperable with the associated inverter (s) inoperable, appropriate restrictions are implemented in accordance with the affected required #eature(s) of the LCOs' ACTIONS.

In many instances, this option may involve undesired administrative efforts. Inerefore, the allowance for sufficiently conservative actions is made (i.e., to suspend CORE ALTERATIONS, movement of irradiated fuel j

assemblies in the(primary or secondaryVcontainment, and any activities that could result in inadvertent draining of

)

thereactorvcssel).

i Suspension of these activities shall not preclude completion of actions to establish a safe conservative condition.

These actions minimize the probability of the occurrence of postulated events.

It is further required to immediately initiate action to restore the required inverters and to continue this action until restoration is accomplished in order to provide the necessary inverter power to the plant safety systems.

Notwithstanding perfomance of the above conservative Required Actions, the unit is still without sufficient AC I

vital power sources to operate in a safe manner. Therefore, action must be initiated to restore the minimum required AC i

vital power sources and continue until the LCO requirements are restored.

i The Completion Time of imediately is consistent with the required times for actions requiring prompt attention. The restoration of the required inverters should be completed as quickly as possible in order to minimize the time the plant i

safety systems may be without power or powered from a constant voltage source transformer.

[

SURVEILLANCE SR 3.8.8.1 REQUIREMENTS This Surveillance verifies that the inverters are functioning properly with all required circuit breakers (continued) st/; ;TO B 3.8-77 Rev.

O, 09/28/92

'd Inve rte rs --Shut down B 3.8.8 BASES SURVEILLANCE SR 3.8.8.1 (continued)

REQUIREMENTS closed and AC vital buses energized from the inverter. The verification of proper voltage and frequency output ensures that the required power is readily available for the instrumentation connected to the AC yital buses.

The 7 cay frequency takes into account the reduncer.+ car, ability of tne inverters and other indications available in tne control room that alert the operator to inverter malfunctions.

REFERENCES 1

fftAR, Chapterl(677~

$fSAR, Chapter 315[

j;--;;s 8 3.8-78 Rev.

O, 09/28/92

Distribution Systems-Shutdown j

3.8.10 1

3.8 ELECTRICAL POWER SYSTEMS dnd/?d'[ue/

3.8.10 Distribution Systems-Shutdown 3 LCO 3.8.10 The necessary portions of the Division >1,-Oi isi;T 2. and h yrstem 3 AC DC,7{and AC vital busf electrical power distributi bsystems shall be OPERABLE to support er,aipment. required to be OPERABLE.

/, Q 3, d, J 'l lsoo.a APPLICABILITY:

MODES 4 and 5, l\\

During movement of irradiaht d fuel assemblies in the II

--[pr%:ry ee secondary ntainment.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.

One or more required A.1 Declare associated Imediately DC,7(orACvital supported re uired AC, %1ectrical power feature (s) an bus}

distribution inoperable.1 4 +5 * ^ 4M,

, rr uired subsystems inoperable.

OE V

A.2.1 Suspend CORE Imediately ALTERATIONS.

AND A.2.2 Suspend handling of Imediately irradiated fuel assemblies in the

[;;ri rj er -

secondary.} *-

containment.

6.N,Q (continued) 1 i

3.8-42 Rev.

O, 09/28/92 BWR/6 STS

)

Distribution Systems--Shutdown j

3.8.10-l ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.

(continued)

A.2.3 Initiate action to Immediately J

suspend operations with a potential for draining the reactor vessel.

AND A.2.4 Initiate actions to Immediately restorer' required P AC, 'DC,7;and AC vital bus} electrical power distribution subsystems to OPERABLE status.

&NQ A.2.5 Declare associated Immediately required shutdown coolingsubsystem(s) inoperable and not in operation.

b r

i r

SURVEILLANCE REQUIREMENTS FREQUENCY t

SURVEILLANCE r

Verify correct breaker alignments and 7 days SR 3.8.10.1 voltagetop{ required}"fC,DC,7{andACvital busPelectrical power distribution subsystems.

L I

f i

3.8 43 Rev.

0, 09/28/92 BWR/6 STS J

e 4

Distribution Systems-Shutdown B 3.8.10 B 3.8 ELECTRICAL POWER SYSTEMS B 3.8.10 Distribution Systems-Shutdown BASES BACKGROUND A description of the AC, DC, and AC vital bus electrical power distribution systems is provided in the Bases for LCO 3.8.9, " Distribution Systems-Operating."

w e.

APPLICABLE Theinitialconditionsof/DesignBasisAccidentand SAFETY ANALYSES transient analyses in the #5AR, Chapterb[6)'IRef. 1) and Chapter %15V(Ref. 2), assume Engineered Safety Feature (ESF) systems are OPERABLE. The AC, DC, and AC vital bus electrical power distribution systems are designed to provide sufficient capacity, capability, redundancy, and reliability to ensure the availability of necessary power to ESF systems so that the fuel, Reactor Coolant System, and containment design limits are not exceeded.

The OPERABILITY of the AC, DC, and AC vital bus electrical power distribution system is consistent with the initial assumptions of the accident analyses and the requirements for the supported systems' OPERABILITY.

The OPERABILITY of the minimum AC, DC, and AC vital bus electrical power sources and associated power distribution subsystems during MODES 4 and 5 ensures that:

a.

The facility can be maintained in the shutdown or refueling condition for extended periods; b.

Sufficient instrumentation and control capability is available for monitoring and maintaining the unit status; and c.

Adequate power is provided to mitigate events postulated during shutdown, such as an inadvertent draindown of the vessel or a fuel handling accident.

The AC and DC electrical power distribution systems satisfy Criterion 3 of the NRC Policy Statement.

(continued)

BWR/0 STS B 3.8-89 Rev.

O, 09/28/92 ABws t s

i Distribution Systems-Shutdown l

B 3.8.10 BASES (continued)

LCO Various combinations of subsystems, equipment, and components are required OPERABLE by other LCOs, depending on the specific plant condition.

Implicit in those requirements is the required OPERABILITY of necessary support required features.

This LCO explicitly requires energization of the portions of the electrical distribution system necessary to support OPERABILITY. of Technical j

Specifications' required systems, equipment, and components-both specifically addressed by their own LCOs, and implicitly required by the definition of OPERABILITY.

Maintaining these portions of the distribution system energized ensures the availability of sufficient power to operate the plant in a safe manner to mitigate the consequences of postulated events during shutdown (e.g.,

fuel handling accidents and inadvertent reactor vessel draindown).

APPLICABILITY The AC and DC electrical power distribution subsystems required to be OPERABLE in MODES 4 and 5 and during movement of irradiated fuel assemblies in theMsecondaryfcontainment provide assurance that:

_ n fm f ll a.

Systems to provide adequate coolant inventory makeup are available for the irradiated fuel in the core in case of an inadvertent draindown of the reactor vessel; b.

Systems needed to mitigate a fuel handling accident are available; c.

Systems necessary to mitigate the effects of events that can lead to core damage during shutdown are available; and d.

. Instrumentation and control capability is available for monitoring and maintaining the unit in a cold shutdown or refueling condition.

The AC, DC, and AC vital bus electrical power distribution

~

subsystem requirements for MODES 1, 2, and 3 are covered in j

LCO 3.8.9.

(continued)

ABWR/fr-STS B 3.8-90 Rev.

O, 09/28/92

r e'

Distribution Systems-Shutdown B 3.8.10 BASES (continued)

ACTIONS A.l. A.2.1. A.2.2. A.2.3. A.2.4. and A.2.5 Although redundant required features may require redundant divisions of electrical power distribution subsystems to be OPERABLE, one OPERABLE distribution subsystem division may be capable of supporting sufficient required features to allow continuation of CORE ALTERATIONS, fuel movement, and operations with a potential for draining the reactor vessel.

By allowing the option to declare required features associated with an inoperable distribution subsystem inoperable, appropriate restrictions are implemented in accordance with the affected distribution subsystem LCO's Required Actions.

In many instances, this option may involve undesired administrative efforts. Therefore, the allowance for sufficiently conservative actions is made (i.e., to suspend CORE ALTERATIONS, during movement of irradiated fuel assemblies in the b r'= f g.7 econdary [ \\\\

containment and any activities that could result in inadvertent draining of the reactor vessel).

Suspension of these activities shall not preclude completion of actions to establish a safe conservative condition.

These actions minimize the probability of the occurrence of postulated events.

It is further required to immediately initiate action to restore the required AC and DC electrical power distribution subsystems and to continue this action until restoration is accomplished in order to provide the necessary power to the plant safety systems.

Notwithstanding performance of the above conservative Required Actions, a required residual heat removal-shutdown cooling (RHR-SDC) subsystem may be inoperable.

In this case, these Required Actions of Condition A do not adequately address the concerns relating to coolant circulation and heat removal. Pursuant to LCO 3.0.6, the RHR-SDC ACTIONS would not be entered.

Therefore, the Required Actions of Condition A direct declaring RHR-SOC inoperable, which results in taking the appropriate RHR-SDC ACTIONS.

The Completion Time of immediately is consistent with the

~

required times for actions requiring prompt attention. The restoration of the required distribution subsystems should be completed as quickly as possible in order to minimize the time the plant safety systems may be without power.

(continued)

M /S STS B 3.8-91 Rev.

O, 09/28/92

[

s -

r c'

Distribution Systems-Shutdown 8 3.8.10 BASES (continued)

SURVEILLANCE SR 3.8.8.1 REQUIREMENTS This Surveillance verifies that the AC, DC, and AC vital bus j

electrical power distribution subsystem is functioning properly, with the buses energized. The verification of l

proper voltage availability on the buses ensures that the i

required power is readily available for motive as well as control functions for critical system loads connected to these buses. The 7 day Frequency takes into account the redundant capability of the electrical power distribution subsystems, as well as other indications available in the control room that alert the operator to subsystem malfunctions.

REFERENCES 1.

S/SAR,Chapterl6]C Aswn-( STSAR, Chapterh[

2.

&Ri6 5ii-B 3.8-92 Rev.

O, 09/28/92