ML20093D152

Forwards Rev 3 to Draft Emergency Procedure Guidelines

ML20093D152
Person / Time
Site:	LaSalle
Issue date:	09/26/1984
From:	John Marshall COMMONWEALTH EDISON CO.
To:	Harold Denton Office of Nuclear Reactor Regulation
Shared Package
ML20093D155	List: ML20093D152 ML20093D156
References
9238N, NUDOCS 8410110123
Download: ML20093D152 (42)

Text

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--[k Commonwealth Edison

) one Fir:t National Plaz9, Chicago, Ilhnois -

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~7 Addr:ss Fleply 12: Post Offica Box 767

\ ,/ Chicago, Illinois 60690 September 26, 1984 Mr. Harold ~R. Denton, Director Office of Nuclear Reactor Regulattun U.S.. Nuclear Regulatory Commission Washington, DC 20555 Sub ject: LaSalle County Station Unit 2 Facility-Operating License NPF-18 Condition No. 4 of Attachment 2 NRC Docket No. 50-374 References.(a): License NPF-18 Attachment 2, Condition No. 4.

(b): August 25, 1983, letter to H. R. Denton .

from Cordell Reed.

(c):- December 15, 1983, letter to H. R. Denton from B. Rybak.

Dear Mr. Denton:

This letter is submitted to comply with a LaSalle County Station Unit ~2 license condition [ reference (a)]. The attachments to this letter const{ute opera ng aprocedure procedures to generation 8 ROG Rev. package 3 to upgrade LaSalle's emergency-Please direct any questions you may have concerning this matter to this office.-

One signed original and fifteen copies of this letter and the attachments are provided for your use.

Very truly yours, bM Wd.d[

J. G. Marshall Nuclear Licensing Administrator cc: RegionfIII Inspector - LSCS

-A. 80urnia - NRR Attachments 1: Technical Guideline - The technical basis for our Symptom oriented Emergency Procedures (LGA's) 2: Writer's Guideline - guidance for the LGA writer 3: Validat!an Description - LGA validation procedure 4: Varification Description - LGA validation procedure 5: Training Description - description of training planned h for the LGA's 8410110123 840926 PDR ADOCK 05000374 i@

9238N F PDR '

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i A Since the Technical Specificatione perant MSIV toolation in hot standby, thle should not require entry into the RPV Control Guideline and a subsequent scram per Step RC-il the entry conds-tion needs to be limited to teolettone ashich require a scram.

Resolved entey condi=

tiene deleted as it le no longer respuired with Radio-activity Release Control Suldeline.

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LSCS-DFSAR 6.3.2.2.6 ECCS Pumps MPSB The ECCS pump specifications are such that the NPSB requirements for HPCS, LPCS and LPCI are met with the containment at atmospheric pressure and the suppression pool at saturation temperature. The NPSB available and required for all pumps in the ECCS are shown in Figures 6.3-3, 6.3-6, and 6.3-9. Vendor tests on ECCS pumps show that I foot NPSH is required for the LPCS pump and 6 feet NPSB is required for the LPCI pumps. The HPCS pump requires 12.5 feet NPSB. Available NPSE is determined assuming suppression pool suction strainers are 50% clogged, i

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REV. 0 - APRIL 1984

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t%i ADN3'3es#3 1 t i i i I a o e e e h o tootus A 31s Nt ov3w iv101 LA SALLE COUNTY ST ATION UPDATED FINAL' SAFETY ANALYSIS REPORT FIGURE 6.3 6 LPCS PUMP CHARACTERISTICS (SHEET 1 of 2)

REV. 0 - APRIL 1984

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lt may not be possible to restore CS or LPCS to the AUTOMATIC / STAND 8Y mode when the ECCS inttistion signal clears the step needs to include the "if possible" phrase f r om Caution etO.

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l Mesolved caution changed by deletion of recautre-ment to restore systems to to AUTOMATIC / STAND 8Y es this may precipitate subsetpJent l

l Rev level control probleest Caution #10 changed stallerly.

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RCIC turbane not system to throttled to easntaan turbine speed above the etnteuel the tore system needs to be i

thenged to tur bine Resolved teutien thenged by substs tutten of tur bine for systen l

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CcUTION e18 If continuous LFCI operation of anv RHR pump is required to assure adequate ccre cooling. do nct divert that pump from the

.LFCI mode.

DISCUSSION:

If LPCI injection is not recutred to assure adecuate cors cooling. It is permissable to ut111:e FHE pumos for ethse functions such *s suppression pool eccling or containment scree.

However. if adequate cere cooling recutres continuous LFCI

. operation with a perttevlar F HF' pump . It shculc not be di'.eetec

.irem the iniection mode. Caetson #1G provides the flegibilits, c8 using one FHF Icop to infect i ntc the RF'/ 'LEC1 meJe) and tne other FHF Icops tc operate in ecme other mode (e.q,. suppression pool cocling) if single Icep LCCI cperetten is sufficient tc ensure acequete C3re C3c11mg.

" Continuous" as used in Ceutscn elG permits.intermittment simv1-taneous use of all FHR pumps in modes of operatic 6 other than LPCI tf adequate core cooling 15 not lost in the interim. Dv alternating modes of RHR operation. assuring edecuate core cooling and protecting containment integrity need nct be mutually elf cl usi ve.

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I" 1-C4vtton #13 is'ecplac+ble to steps ci the EFGs where the F.H R System is to be coerated in a mode other than LFC: and contain-

[ ment' . integrity'is not taimediately threatened. Where civerting I' the .EHP Svstem f roin the LFCI mode is absciutely

[ recuired ,to J.

protect .centainment integrity, the wording "terespective of adequate core ~ cccling" is included in the EFG step to l specificall, highlight the non-soplicab111t, c4 Ceutten a19.

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t' The present step could be accomplished by initiating only one of the lasted functions /systdest at needs' to be rewor ded to require confirmatson or initiation of all functions / systems tehi ch should have initiated.

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tence and substitution of "Ini tiate each of the fol-1outng elch shoutd have initiated but did not!"

for first swtonce.

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F Contingency 87 should be enteeed enhenever boron has been injected snto the RPVI the entry condition needs to be expanded from "Doron Injection is required" to "Soron injection is required or has been inttleted."

Resolveo bones changed by addition of "or baron has been injected into into tha RPV".

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' STEP:

RC/L-3 When [ procedure for coolcown te cold shutdown conditions 3 is enteeed from Cstep RCfF-5].

pr.oceed to cold shutdown an acccedence with

[ procedure for-cooldown to ccid sh.ttcwn .

conditions 3.

DISCUSSION:

Aftcr RF / pressure nas been reduced to_below the shutdown cooling 1ntGrlocts and 'the shutdown cooling mtde of RHR has been (C$tcblished. normal operating procedures provice the appropriate 90tructions tor continued chntrol cf RFV water level while procOOding to cold shutdown conditions.

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7.4.2 Coerator Actions (RC/P)

STEP:

RC .' F- Monitor end control F.FV pressure.

l If while e:: ec ut i ng the following steps:  :

o Emergency FF'V Deceessurt

etion is -----

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! enticipated and Beren Injection,is not  : #10 :  :

l' required, repidly depressert:e the FF'V -----

with the mein turbine bvpess velves.

e DISCUSSION:

f ailure to ter m1nete end pr everet injection 2nto the RFV

( e r. c ep t v r orn L.o on 1:ej e ct 1 ore t y5 t eens eind CRD) mey result in the r 4.p i d ' a r:J ec t i o,i e o+ - 1 c r g e- vol urries of r el e t i vt-1 y cold. unt.or eted weter tree low pressure s, sterns as M V pressure decreases end cropt be1ow the shutcff heecs of the purr @ s in these svstems.

h.c h er oc curr ence. covid dilute borori coricentr et t on end reduce weter temper et ur e in the cur e regi cre, ther eby edding s u f f a c l e-n t tiet p e sa ti ve. reactivity to induce e. Yecctc.r power encurston which could deniege the core.

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Loss- of the centinueus SEV pneumatic suppay limits the numter of times that en SAV cco be cycled since pneumstic pressure is reqvtrec for. velve opeestacq. Even though the bEV SCCumulators Co9 thin & reEEeVe pneuMet1C scpply. leelage through in-line valves end fattings mey deplete this sepply. Thus.

subsequent to the loss,of the centanuous SRV pneum + tic supply, there i s no assur ance as to the number of SPV oper# ting cycles remaining.

For these ressons, if SRVs must be usec to augment RPV pressure control +nd if the con-tinuous SRV pneumatic supply is or becomes unav al l ebl e, the valve should tie closed to limit the numbee of cycles on the valve and conserve pneumatic pressure so that af Emergency Depressuri:ation is subsequently required. the valve will be evea lable +or this

. purpose. If other pressure control systems are not capable of maintaining RPV pressure below the lowest SRV lifting pressure, the SPV will still open when its lifting pressure is reached.

Nelc. LChen h R. V's O.f t b es n j W #E herm uriu , O ud- a \eil cP d-

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Rod i nser t i on cri teri a should be

.. " rods at or beyond (06..", I not " . .r ods beyond 106..".

Resolved alI re4eronces to rod insertion criteria changed to "..at or beyond (06..".

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lit i STEP:

-RC/O-4 If the. reactor cannot be shutdown oefore ----

suppression pocl temperature reaches - the l #19 :

Boron' Injection Initiation Temperature, ----

BCRON INJECTION IS REQUIRED 1 inject boron into the RFV with SLC and prevent automatic initiation of ADS.

. . . Boron 100 * . Injection-

. Initiation

^ Suppression  : . Temperature Pool 100 + .

Temperature  : . -

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110 + .......

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O. I 2 3 4 5 o 7 Reactor Power ( Y. )

DISCUSSION:

Se long as the core remains summerged (the pref errec method et cd2quate core cooling), fuel integrity and RPV i ntegrity are not

< dirCctly challenged even under scram f ailure conditions. A scram

.follure coupled with-an MSIV isoletion. however, results in a

.rcpid heatup. of the suppression pool due-to the steam energy diccharged from the-RPV'via the SRVs. The challenge to contain-m;nt thus'becomes the limiting factor which defines the require-GCnt.for. boron injection.

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tho' suppression temperature anc FFV pressure cannot be re-trCd and maintained below the He+t Capacity Temperature Limit.

rg;ncy RPV Depressurs:ation is required (Step SPIT-4). To Sold depressuri:ing the RPV with the reactor at power, it is 01rcble to shut down the reactor through borcn injection prior roaching the Heat Capacity Temperature Limit. The Baron jcction Initiation Temperature is defined 40 as tc achieve this hcn'procticable.

35 inattation may result in the injection of large vclumes c4

• 10ti v0l y cold. uncorated water from low pressure injection

,pOtom3. With the reactor either critical or shutdown on soluble ort , the pcsttive reactivity addition due to boron c11ution and hmparcture r e.d u c t i on may result in a reactor power eacursion ading to substantial core camage. Defeating ADS is therefere

[propriatewhenever p Bcron Injection-is requirec.

)Cp 'RC/Q-4, coes not limit the operator to resetting the 4D5

.)ncr ca was the limited action specified i n Step RC/L-C; other jthods are to be employed here to permanently defeat the auto-tic f urictioning of ADS at leest as long as reactor shutdown is 3'nti ngcnt upon in-core boron concentration.

k? Cpplicability of Caution #19 1s indicsted at this step to hCOCrv3 J the SLC pumps should they subsequently be needed.

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m The manual scram should be inttnated only after the SDV has had a chance to drains the step needs to ref lect this waiting period.

Resolved changed atop to read "Dr a i n t he sc r ee di s-i l charge volume and initiate a manual reactor scrael

• util-itses to discuss proposed change with operators and pre-l pare for discussion at nemt EPC meeting.

Resolved 5/10/84: stop changed as proposed.

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STEP:

SF/T-4 If suppression pool temperature cannot -----

be maintained below the. Heat Capacity  : # 8 :

Temperature Limit, maintain RFV pressure #13 :

below the Limi t; enter Cprocedure #14 :

developed from the RFV Control Guideline] -----

at CStep RC-13 end er:ecute it concurrently with this procedure.

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DISCUSSION:

Continued heatup of the suppression pool may ultimately result in exceeding primary containment design temperature limits or in

. reducing suppression pool heat capacity below that required to assure stable steam condensation. The Heat Capacity Temperature

' Limit-(HCTL) defines the operating regime which assures continued operation within these limits. Exceeding primary containment design temperature limits may result in containment failure due

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te excessive theemal loacs on the containment snell or to deslure of' equipment located within the containment. Unstable steam condensation produces extremely high dynamic pressure loads on the- ~ containment shell and- submeged structures, generally resulting in failure of the conteanment and loss of the

-containment function. Step SP/T-4 speciftes the ection recutree to _ adequetely addr ess these concerns.

.If_the actions performed under-Steps SP/T-1. SP/T-C. and SP/T-3 are insufficient to'metntain suppression pool t s.np er a tur e below the HCTL. control of the other- parameter, RPV pressure, is effected' through entry into the RFV Control Guideline and execution of the RFV pressure control steps specified therein.

The . instruction specifying entry into the RPV Control Guideline is explicitly stated here because conditions requiring entry into the Primary Conteinment Control 'Guidel t ne do not necessarily also

-require entry into the RPV-Control Guideltne. Entry at Step FC-1 essures ' concurrent control- of the three interrelated RPV peremeters (RPV water *1evel, RFV pressure, and reector power).

Ceution #9 is identified as'being applicable at this step because of the relationship between high suppression pool temperature end pump NPSH.

Caution #13 is identified as being applicable et this step to highlight the possibility that the rate of RPV pressure reduction

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l required to remaan below the Heat Cape Ity Temperature Limit may I result 'in.' exceeding the _ Technical Specificaticn' limit for cooldown rate.

Caution 84 1' 4 is identified as being applicable at this step to

-assar e en et proper consideration i s given to maintaining adequate core i coc11ng. .

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N STEP:

-SF/T-4 If suppression pool temperature and F.PV pressure cannot be restored and maintained below the Hest Capacity Temperature Limit, EMERGENCY FFV DEF F.E S-SURIZATION IS REDUIRED.

DISCUSSION:

Once. it is concluded that the preceding actions are insufficlent

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to restore- and maintain suppressi on pool temperature and RFV pressure below the HCTL. -depres'surication of the RPV is' manually initiated while the heat capacity of the suppressien pool remains

. sufficient to safely accommedste the bicwdown. As oiscussec earlier,- the consequences of.not depressurl:1ng the RPV when required may include failure of equipment important to sa4ety, loss of_ containment' integrity, loss of the pressure suppression

. function of the primary containment. and loss of the water supply tolthe ECCS pumps, all of which may also lead to inadequate core cocling. ,

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O STEP:

If owhile e::ecuting the .f ollowing steps sup;ressicn pool :

sprevs have 'been initiated, when suppression chember :

pressure drops *below Q psig. ter mi nate suppression pool :

spr ay s .- l

(- _________________________________________________________

DISCUSSION:

Once suopression pool spr$'.s have been ' initiated, c o n .*e c t i v e

- cocling- may gradually depressurl:e the containment to below its

- design

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negative pressure esen though containment pressure was above the Mark III Containment Soray Initiation Fressure Limit when sprays were initiated. This is the result of the event-upacific . criteria emploved to s1ce the atmosphere-to-containment

. vacuum brealers, if'any. Terminating suppression pool sprays when suppression chamber pressure drops below 0 psig terminates the depressurt:ation before the design negatt.e pressure is

-exceedec. -

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10.2 Entry

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The entry condition for this guideline is:

o Offsite radioactivity release rate above the off site release rate which requires an Alert.

DISCUSSION:

The entry _ condition for the Redicactivity Release Control Guide-line directly relates to the purpose of the guideline and pro-vides the vehicle for coordinated execution of emergency operating procedures and the emergency plan. The specific value selected fer this entry condition corresponds directly to an action level in the emergency plan. It i s sufficiently high that it is not e: pected to occur during normal operation but sufficiently low that, of and by itself. it does not threaten the health and safety of the public.

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STEP:.

RR-2 If-offsite radioactivity release rate approaches or er.ceeds the offsite release rate which requires a General Emergency and-a primary System is discharging into an area outside the primary and secondary containments, EMERGENCY RPV DEPRESSUR12ATION IS REQUIRED: enter [ procedure developed from the RPV Control Guideline 3 at CStep RC-13 and e:: ecut e it concurrently with this procedure.

DISCUSSION:

Depressurizing the RPV immediately reduces the driving head and flow from primary systems that are discharging outside the primary'and secondary' containments.

The instruction to enter the RPV Control Guideline provides the mechenism by which Contingency #2 (Emergency RPV Depressuriza-tion) is reached. Refer to Section 7.4 for a discussion

-regarding entry to Contingency #2 from the RPV Control Guideline.

Entry at Step RC-1 ensures that a reactor scram is initiated and assures concurrent control of the three interrelated RPV parameters (RPV water l evel , RPV pressure, and reactor power).

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The bon folloeing the table should precede it (or else "f ollowing" should be changed to " preceding") and should include the step requiring prevention of automatic initaatton of ADS.

3-Resolved bt*s moved to precede Step Cl-35 bou in-cludes stop requiring prevention of automatic initiation of ADS.

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STEP:.

Elf PPV-Floccing is required. enter. L pr ocecure cevel oped i

trom' CONTINGENCY #oj. l C2-2 Enter 1[procedur e developed + rom; the hFV Control buldeline]

el L S t ep F C / F '.' 3 . .

DISCUSSION:

'With F?V depressert:atiori complete. Cont irigenc y #2. i s e::l ted. Ii

. plant c endi t i oris 'ealet which. r equire RFV F1ooding (entry tc C,ont i nger ac y 42 wes .ec;..irric it FF V Fl obdling ws s . r ecui red end

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- s iu r. 6 4 r c t . op ei .- SF 's ' w c h lest t h er. tb- riun bet - or SRVs dect i c e l ed to

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- A.L*S e . T r ur thc' 1 re s tr uc t i or:L tor FFV pr essur e contr el er e specifiec i s. - Cont i r ueric s #c. Other wi se. the RFV pressure'contiof steus of the FFv Constrel beidellem p r' ov i d e the eppeopr14te instructicms

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if ca ' c otill eiva s.g cosit rol of RFV pressure.

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T The language in the first bon refers to the the f ol loosing steps," but there is on!y one step in tpta contingencyl thie language needs to be changed to "this step."

Resolved cnreged as proposed.

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TT All other pumps (except CRD and bor on injection systems 4713 should be secured prior to this step.

Resolved now stop CS-5 added.

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U STEP:

C6-2 If any control rod is not inserted beyond position CO6 (maximum subcritical bant:ed withrawal position)3:

C6-0.1 -Terminate and prevent all injection into the RPV except from boron injection systems and CRD until RFV pressure is below the Minimum Alternate RFV Flooding Pressure.

l l Minimum Alternate RPV  :

Number of open SRVs Flooding Fressure (psig)

C 7 or more  : 110 3  :

C6  : 135 3  :

C5  ; 165 2  :

C 4 1 210 3  :

' C 3  : 080 J CO  : 4!.O 3  :

C1  : 870 3 l If less than C1 (minimum number of SRVs for which the Minimum Alternate RPV Flooding Pressure as .

below the lowest SRV lifting pressure)J SRVCs] can -

be opened, continue in this procedure.

DISCUSSION:

If'any control rod is not inserted beyond the Maximum Subcritical

.Bant'ed Withdrawal Position, the reactor may become critical during the flooding evolution. The consequences of a return to

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e criticality -during plant cocidewn are generally mana;eetle but

'here. .where the-cooldown may be_very rapid and the criticality m a y. occur with the RPV solid. these consequences could include significant damage to both the core and the RPV. Thus RPV flooding under these conditions must be accomplished in a manner which carefully controls the rate at which positive reactivity is added to the core.

.Before- the FPV as flooded it should. if at all possible, be depressuri:ed. This increases the number of systems which may be used for flooding and decreases the pressure at which the SFV5 and associated Cischarge piping must Accommodate the flow of twG-phase and subcooled water. However, a rapid deprescurl:ation of the- RPV may result in the rapid injectici, of large volumes of relatively cold, unborated water from low pressure injection systsms as. PPV prew:ure decreases and drops below the shutoff heads of t h e p uri.,m s in these systems. Thus all injection into the 10%' mest. .be terminated and prevented prior to commencing the -

rapid depressuri:etions this sequence of actions is specified by this s t'eg in conjunction with Step CC-1 of Contingency #2 (Emer-gency RFY Depr es sur i : at i on) . Injection from .bohon injection systems. and CFD is not terminated here because boron injection systems add negative reactivity and CRD is required to manually.

insert control rods.

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l So. long aslRPV' pressure remains above the Minimum Alternate RPV Flooding Pressure, the core is adequately cooled by a combination of ' submergence and steam cooling irrespective of whether any water i s being injected into the RPV. This is so because the

. Minimum Alternate RPV Flooding Pressure is defined for a given number- of open SRVs to be the lowest RPV pressure at which steam flow up through a completely uncovered core and out the SRVs can adequately cool the core by heat transfer to the steam alone. Of course if this steam flow e::i sts and the core is also pertially submerged, which would be necessary to maintain this steam flow and a constant-RPV pressure. the entire core is that much cooler. .

Once PPV pressure, drops below the Minimum Alternate RPV Flooding Pressues. the rate of depressuri:ation is small and inje: tion into the RPV must be re-established in order to adeauately ccol the cort and ultimately flood the RPV. If less than the minimum number of SRVs for which the Minimum Alternate RPV Flooding Pressure. is-below the lowest SRV lifting pressure can be opened.

then injection into the RPV must be re-established without delay for the same reasons.

S

V STEP:

C6-0.3 Maintain at least [1 (minimum number of SRVs for which the Minimum Alternate RPV Flooding Pressure is below the lowest SRV lifting pressure)3 SRVCs]

open and RPV pressure above the Minimum Alternate

'RPV Flooding Pressure but as low as practicable by throttling injection.

DISCUSSION:

As discussed under Step C6-2.0, throttling injection to maintain RPV pressure above the Minimum Alternate RFV Flooding Pressure assures that either the RPV will flood to the main steam lines or, if the reactor returns to criticality, the core will be adequately c ool ed by a combination of submergence and steam cooling. RPV pressure should be maintained above the Minimum Pressure but as low as practicable to minimi:e the flooding rate and accoinpanying theemal end hydraulic 1 cads on the RPV as well as the dilution of any boron i n the core region. -

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STEP:

C6-3 If RPV water level cannot be determined:

-C6-3.1 Commence and increase injection into the RPV with the following systems until at least C3 (Minimum Number of SRVs Required for Emergency Depres-suri ation)3 SRVs are open and RPV pressure is not decreasing and is C77 psig (Minimum RPV Flooding Pressure)3 or more above suppression chamber pressure.

o HPCS o Motor dri',en feedwater pumps o LPCS em LPCI o Condensate pumps o CRD Co RHP service water crosstie 3 to Fire System 3 Cc Interconnections with other units 3 to ECCS Leep-full systems 3 to S'_ C (test tank) 3 Co SLC (boron tank) 3 DISCUSSION:

If RPV water level can be determined. Step C6-4 specifies the appropriate actions for RPV flooding and Step C6 ~ is bypassed.

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For plant conditions where RPV water level cannot be determined.

RPV pressure indication is utili:ed to confirm that sufficient water- is being. injected into the RPV to flood it. The Minimum l

RPV Flooding- Pressure is defined to be the lowest differential I 1

pressure between the RPV and the suppression chamber (and thus across .the open SRVs) at which steam flow through the Minimum tJumber of SRVs. Required for Emergency Depressuri:ation is

. sufficient to remove all decay heat generated within the core

(; with no steam superheat (i.e., by boiling heat transfer alone).

The.. decay heat generation rate used in mal:ing the det ermi nati on of this Minimum Fressure is that which corresponds to core condi-

.tions ten minutes after a scram from full power. Since ten minutes is the earliest RPV Flooding could reasonably be e::pected t'o be required. ' establishing and maintaining RPV pressure abcve the Minimum RPV. Flooding Pressure assures that more than enough steem flows through the SPVs to carry away all core decay heat.

.This in turn requires that more than enough water to carry away

-decay heat by boiling reaches the core, and this requires that RPV water level increases. Maintaining this Minimum Pressure (and .thus steam flow) thereby assures that the RPV will ul timatel y flood to the main steam lines.

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M Therefore.. .three conditions must be sat 1sfied to verify RPV Flooding without direct indication of RPV water level:

1. RPV pressure must be greater than suppression chamber pressure by at least the Minimum RPV Flooding Prescure.

This ensures more than enough steam is flowing through the'SRVs to remove all decay heat.

2. RPV pressure must not be decreasing. This ensures that

- the requisi te steam flow will be maintained.

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3. At 'least the' Minimum Number of SRVs Required for Emer-gency Depressurization'must be open. This ensures that the requisite steam flow will entst when the RPV is i 1

l above the Minimum F.PV Flooding Pressure.

l t-This= step requires'that injection into the RPV be increased until t

all three'of'the above conditions are satisfied.

The' list of injection systems identified in Step C6-3.1 centains .

• 11 of the motor-driven systems which may be used for injection ir.to .the RPV.. As many of these systems as necessary should be used to establish and maintain the three conditions required for verification of RPV Flooding.

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)A 17.3 Coerator Actions

-STEP:

If while e::ecuting the f ollowing steps:  :

o RPV water level cannot be determined. RPV FLOODING IS :

REQUIRED: enter.Cprocedure developed from CONTINGENCY #63. !

! o RPV Flooding is required, enter Cprocedure developed from :

CONTINGENCY #63. l DISCUSSION:

The actions specified in Contingency #7 require the abilitv to

. determine RPV water level. When RPV water lesel cannot be deter-mined. RPV Flooding is required to assure continued adequate core cooling. RPV Flooding is also required for the plant conditions listed in Table 16-1 in Section 16. If RPV Flooding is required, the appropriate steps to accomplish th1s evolution are contained in ContingencyL#6. ,

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l The means by which RPV. water lesel is deliberately lowered is the termination and prevention of injection into the RPV. With the reactor at power, coolant d nventory is lost by steam flow through

. on e oor more open.SRVs-(or through a break). If the inventory 3

,,-iffloss 1,s not made up, RPV water level will decrease by boiloff.

Injection from boron injection systems and CRD is not terminated

'here because boron injection systems add negative reactivity and CRD: i s required to manually insert control rods. Further, the 2

flow rates- +t cd these systems are small compared to the boiloff rate with;the-reactor at power.

.g - 'RPV water' level is allowed to continue to decrease until either:

1. The. suppression pool heatup,is terminated or reduced to 'near that which resilts from absorption of decay heat. or

2. RF;V : water level has decreased to the ' Flow Stagnation

. . i Water Level, defined to be the higher of either.the top

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of the active fuel or the elevation at which natural _

circulation flow in the RPV _ stagnates.

If the suppression pool heatup is terminated J+ em ced to near that 'which results from'the absorption of n.ca) cat, as in-dicated by reactor power below the APRM downscale trip setpoint or the combination of all SRVs closed and drywell pressure below

the high drywell pressure scram setpoint, the potential for

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Z The portton of the step which dir ects the oper at or to maintain RPV water level above TAF needs to restract him to the use cf the systems 16 sted earli er in this step.

Resolved step Changed by addition of "with these systems.*

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AA STEP:

C7-4. When Cprocedure_for cooldown to cold shutdown conditions 3 is entered.from Cprocedure developed from the RPV Control

' Guideline 3 at CStep RC/P-R3, proceed to cold shutdown in accordance with Cprocedure for cooldown to cold shutdown conditions 3.

DISCUSSION:

After RPV pressure has been reduced to below the shutdown cooling interlocks and the- shutdown cooling mode of RHR has been established, normal operating procedures provide the appropriate instructions for continued control of RPV water level while proceedirg-to cold shutdown conditions.

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