ML20236U132

Review of Smud Emergency Operating Procedures

ML20236U132
Person / Time
Site:	Rancho Seco
Issue date:	11/17/1987
From:	Book T BABCOCK & WILCOX CO.
To:
Shared Package
ML20236T959	List: ML20236T956 ML20236U132 ML20236U139
References
51-1170856, 51-1170856-00, NUDOCS 8712020301
Download: ML20236U132 (38)

Text

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i REVIEW OF SACRAMENTO RJNICIPAL UTILITY DISRICT'S EMEIEENCY OPERATING PROCEDURES 1

by T.L. Book Sr.

Systems Design & Instrumentation Engineering

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BABCOCK & WILCOX Nuclear Power Division 3315 Old Forest Road P.O. Box 10935 Lynchburg, Va 24506-0935 51-1170856 00 hok0$f)$0k$ho 2 Pace 2 of 31 F

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- N O EM EN2iNEERING INFORMATION RECORD -

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1170856-00 ,

Document identifier 51 Title Review Of !DED's EOPs PREPARED BY: REVIEWED BY:

Nrme T.L. s k sr. Name . B.L. Brooks _

signatur M -

Date # 7 Signature I

I Date //,[/7h7 Technical Manager Statement: Initials Reviewer is Independent.

Romarks: (see Attached)

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BABCOCK & WILCOX 4

liUQ. EAR POWER DIVISION 1

LYNCleURG, VIRIINIA

" REVIEW OF SR10'S E0Ps RELATIVE TO TBD INTENTIONS" alMDB8CI A rev iew of the Sacremento Municipal Utility District's (SMUD's) Emergency Operating Procedures (EOPs) was undertaken relative to the Technical Bases Document (TBD) intentions. A systematic rwiew of each E0P step was cade. The k review sought to ascertain whether these steps correctly reflected the TBD intentions. The reason \ for the review was to verify compliance of SMUD's EOPs l with the TBD intentions as well . as hiake some prediction of re-start readiness of these procedures. The result of this review is that SMUD's EOPs general'ly meet the intentions of the TBD and, relative to TBD intention s, pose no identified re-sta rt problems. After resol ution of the comments listed in j I

Appendix A of this report, their EOPs will be in functional compliance with ]

current TBD intentions, based on B&W's literal interpretation of the' ECPs.

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51-1170856 00 Page 3 of 31

--_-_-a

TAILE OF. CONTENTS I

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PAGILita.Ea I. INTRODUCTION 1 i-i 2

'I II. METHODOLOGY I

III. COMENTS 3 l t

ll IV. CON (10SION 4

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l Y. REFRENCES 6 APPE)OIX A " LIST OF SPECIFIC C044ENTS" 8 i

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i I. INTRIluCTION ,

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The Emergency Operating Procedures (EPs ) are a critically igortant part of I l

successful and safe power plant operations. The ECPs used at the Sacramento .l Municipal Utility District's (SMJD) Rancho Seco Nuclear Power Plant (see Ref. -

V.8.) are based on generic guidelines. These ; guidelines, known as - the Technical Bases Document (see Ref. V. A. ), were developed for SMJD by Babcock &

Wilcox ( B&W ) . The purpose of this review is to determine if the ECPs reflect the original intent of the TBD thus providing some indication of Rancho Seco's procedural readiness for restart.

This review does not rep resent a validation ef fo rt. 'It is more rightly a ve ri f ication of TBD intentions relative to B&W's literal inte rpretation of j 1

SMUD's EOPs. As such,'it is limited in scope to only the E0Ps and their j transitional Cooldown Procedures (cps). Because th is was a short term limited l

effort, a more rigorous, detailed assessment of TBD intentions is advisable.

One element of such an assessment is training; it is not possible to fully evaluate the EOPs without k n ow i ng how they are taught and - how they are interpreted by the operators. Other important elements of a further assessment would bo EOP impact on operator burde.n, cause and effect relationships, review l

of perceived drastic actions and their alternatives, and procedure hierarchy. j I

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II. E"MIMLGRY  :

l The first step in the review of the SMUD E0Ps was an on-site data gathering meeting. At this meeting, the version (revision) of the procedures to be I

reviewed was def in ed. Also, one line flow drawings and related data were obtained. All other data required to perform the review was obtained from the SMUD dedicated team library, located at the WD in Lynchburg, Va.

i The second step covered tha rev iew phase. It was performed by a Principal j 1

Engineer of the Systems Design & Instrumentation Engineering Unit (the group I responsible for original preparation & maintenance of the TBD). The review was conducted in a systematic step-by-step approach. Eve ry step in the procedures was reviewed. The 1BD intentions rel ative to' each step were considered. ]

Discrepancies and othAr questionable items were l isted as c e ments. Each I comment included the following:

1. E0P/CP section identification & title.

2. E0P/CP comment number.

3. Description of comment 3 l

4 Discussion of comment with any recommendations. '

The comments were then reviewed by a Supervisory Engineer of the Systems Design

& Instrumentation Engineering Unit. After discussion with the writer and 1

revision if required, these draft comments were rent to SMUD. This was done in ,

l order to expedite any requi red E(P changes prior to re-start. Finalization of )

1 the ccaments came after clarification discussions with Sf4JD. i 2 51-1170858 00 Page 6 of 31

1 III. G M ENIS j A. CONTAIMD(T TBD INTENTIONS COWENTS  ;

Containment related TBD intentions were considered. However, this was on1 l done with respect to those procedures included. in this review (EOP/ cps). Fe-l the BWOG response to related AT(Xi SER concerns (containment - see Ref. V.C.  : 4 j

1 it was stated, "The generic Technical Basis Document wil1 provide inportar t factors to be conside red by each utility in establishing plant specif':

p roced u res ". Emphasis was placed on pl ant s pecific proced ures and bases.

l Therefore, even though there were no TBD containment discrepancies found as a result of this review, SMUD should pursue this issue further. This is becaust it was not possible to fully review the TBD containment intentions without including all related p'lant specific procedures and bases.

1 B. BM.ANCE OF TBG INTENTIONS COMENTS i There are 15 comments doctrnented in Appendix A. They can be categorized in the following way:

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I EOP/CP SECTION MDEER OF C30ENTS I E.03 - Loss of Subcooling Margin. 3 E.04 - Loss of Heat Transfer. 2 E.05 - Excessive Heat Transfer. 1 i E.06 - Steam Generator Tube Rupture. 5 ICC - Inadequate Core Cool 1ng. 1 3 51-1170856 00 Paae 7 of 31' I

CP.101 - A Large LOCA Has Occurred- 1 And The Core Flood Tank .

Is Emptying.

Rule 2 - Control HPI. 1 Rule 6 - Reactor Ysssel Pressurized 1 Thermal Shock (PTS)

Conside rat f ons.  !

Total 15 1

All comments and their details are found in Appendix A IV. CONCLllSION

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I Of the 15 comments identi fied by the review [ only two represent significant conce rns. They are CP.101-1 and E.05-1 (refer to Appendix A for detailed 4 N

explanation of each comme nt) . Although these' two comments may present some difficulty in the control of abncrmal transients, they do not pose a threat to successful transient mitigation. All the comments, including those not mentioned here, represent deviations relative to TBD intentions and should be considered for implementation into the SMUD E(Ps.

CP.101, as currently written, requires the operator to make a determination of which- Core Flood Tank line, if any, has failed. .This is not requi red by the TBD. The p roced ure causes ad d itional operator burden and could lead to operator errors. Howeve r, if the operator follows the TBD guidance, operator 4 51-1170.856 00 >

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burden is reduced and the core Jis still,; adequately cooled. Therefore, '1 i

sine 11fying the procedure to be in compliance with the TBD intentions will. j increase plant safety while eliminating a possible source of operator burden. l and error.

1 E 05 includes an instruction to trip all feed punps still supplying feed to the I 1

OT$Gs if certain criteria are met. These critoria may bc too restrictive. See j detailed comment, E.05-1, for explanation of this concern'. The criteria for  !

I this required pump trip should be reviewed and revised as necessary.

This TBD intention review found nothing that would render the SMJD EPs unsafe and, therefore, unfit for restart. The SMJD 50Ps need only to incorporate the comments delinehted here to be in functional compliance with the TBD intentions based on B&Ws literal interpretations of the E0Ps.

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l V ., REFERENES A. Emergency Operating Procedures Technical Basis Document l 74 1152414-00.

8. Plaat Operations - Emergency Procedures E.01 Immediate Actions Rev. 2 06/19/87 '

E.02 Vital Systems Status Verification Rov. 5 07/10/87 E.03 Less Of Subcooling Rev. 3 07 /10/87 E.04 Loss Of Heat Transfer Rev. 7 07/10/87 l

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E.05 Excessive Heat Transfer Rev. 9 .07/10/87 E.06 SGTR Rev. 7. 07/10/87 E.07 ICC Rev. 5 06/19/87 CP.101 A Large LOCA Has Occurred Rett . 4 06/19/87J

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And The Core Flood Tank c

Is Emptying. )

1 CP.102 Normal - Cool down Rev. 2 06/22/87. O CP.l'03 Transient Termination Following Rev. 4 06/22/87-An Occurrence That Leaves The RCS Saturated With OTSG(s) Removing Heat.

CP.104 Transient Termination Following An Rev.'4 07/1 0/87 j Occurrence That Leaves The RCS Being Cooled By HPI Cooling.

CP.105 Transient Termination Following An Rev. 3 06/22/87 g .0ccurrence That May Require Pressurizer Recoverf - Solid Plant Cooldown'

'l With OTSG Removing Heat And RCS Subcooled. -

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Rule 1 Initiation Of HPI Rev. 1 02/18/87 i

Rule 2 Control of WI Rev. 3 06/22/87 ..

Rule 3 Auxiliary Feedwater Rev. 3 06/22/87 I Rule 4 OTSG Level Setpoint 'Rev. 2 02/18/87 i Rule 6 Reactor Vessel Pressurized Rev. 2 06/19/87 i Thermal Shock (PTS) Considerations 51'-1170856 00 6 .Page 10 of 31'

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C. Eisenhut, D. G., " Safety Evaluation of Abnormal Transient Operating * --

Guidelines (Generic Letters 83-21) , " Letter From D. G. Eisenhut to all ,

Operating Reactor Licensees, Applicants for an Operating License and Holders of Construction Permits for Babcock & Wilcox Pressurized Water Reactors, September 19, 1983.

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APPEleIX A

1. LIST OF SPECIFIC CCBSENTS8

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l SECTION: E.03 Loss 'of Subcooling E.03-1

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-l DESCRIPTION: Step 6.0 '" Isolate all . possible RCS leaks" R

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mitigation of loss of subcooling transients. Tne actions of E.03 ~

step 6, closing of certain valves, can . be - ef facted quickly from, j the main CR and inpose no undue operator burden. Because these actions may mitigate the transient quickly, they were placed in the TBD with the RC inventory control section which occurs 'second only to RCP trip following symptom identification. However, E.03  !

I step 6 occurs after the ' operator has been directed to enter E.05 '!

to treat excessive heat transfer. 'Because of this, any. isolable RC  ;

1 inventory loss th rough these paths may not be isolated for a considerable period of time, l s

$ For these reasons, SMUD should consider. moving the actions of. E.03 step 6 to follow E.03 step 3.2 j l

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1 SECTION: E.03 Loss of Subcooling MBEER: E.'03-2 DESCRIMTON: Information Step 3.4 DISCUSSION: This information step discusses th's need to maintain continuous i

AFW flow while raising level setpoint to 955. The 1BD, in Chapter

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'IV.C.4.4.3, provides information regarding the need to maintain at .

1 le as t 150 . gpm AFW flow to each SG until the loss' of subcooling i setpoint is reached if incore thermocouple are not decreasing.

l This information is contained in SMUD's E0P rul es . SMUD shoul d-

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consider adding this information .to step 3.4 on 'Information Page E.03-2. Please note that the 'TBD also includes a provision for incore thermocouple response. A proposed change is in Eprocess to r emove this provision, therefore, SMJD should not incorporate any thermocouple response modi fiers in the minimium flow requirement.

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SECTION: E.03 Loss of Subcooling MmeER: E.03-3 l

DESCRIPTION: CP.104 Step 7.2 (Go to this step from E.03 step 10.2) l; DISQlSSION: This E.03 comment is rolated to CP.104 step 7.2 by way of the flow i

path from E.03 step 10.2.

In E.03 step 10.2 the operator is directed to go to CP.104. The (

operator is directed to do this after determining.that the RCS is I

saturated and the incore T/C cool down rate is greater than ]

100F/H R.

CP.104 steps 7.1 & 7.2 state: l 7.0 If AT ANY TIME:

1. The incore T/Cs indicate that the RCS subcooling margin is reestabl ished with FW and SGs still available and l

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cooldown rate is < 100F/HR than go to step 10.0.

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B l 2. The RCS is saturated w FW to OTSGs is restored after l entering CP.104 without FW, than go to step 9.0.

Part 7.1 of this step rightfully makes provision to utilize SG(s)

to augment HPI core cooling in the event that M.e cooldown rate I drops below 100F/HR. This will be accomplished if the RCS has 1

become subcooled. - Part 7.2 addresses the situation where the RCS remains saturated. It allows use of SG(s) to augment WI cooling only if arriving at this point and restoring feedwater in CF.104 ,

l (this p roced ure ); it makes no re fe rence to cooldown rate.

Howeve r, it is possible to arrive here after determining in E.03 step 10 that the RCS is saturated and the incore T/C cooldown rate is greater than 100F/HR. As long as the cooldown rate remains greater than 100F/HR, there is no need to establish heat transfer 51-1170856 00 l

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. 1 M3eER: : E.03-3 Cont'd to the SG(s ). However,. it ' i s possible sometime after entering CP.104, - f rom E.03. step 10.2, for tht cool down1. rate to ' slow witn ,

the RCS still saturated. That b is , - a partially . failed open pressurizer code'.. safety could reseat, the creak may be -isolated,

- a subsequent loss of: one HPI pump raay occur,' etr:.l For those kinds of occurrences, depending upon . th'e' void' fraction at the time, saturated RCS conditions 'may persist for long periods.

During these periods it will be very Ldesirable to augment WI heat .

removr.1 ~ with SG(s) heat transfer, thereby mair.tainingjhe greatest allowable cooldown rate. Further, for some cases, such as loss of an HPI pump, SG(s ) . augment?. tion will be even more desirable as cooldown time may take con.siderably longer. in this situation.

- g j It is recommended that SM'O. change CP.104 step 7.0 to reflect these concerns. A possible change would bet - l N d 7.3 The RCS is saturated with SGf s) operable, and cooldown -

rate is less than 100F/HR, -then go to step 9.0.

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SECTION: E.04 Loss Of Heat Transfer ElleER: E.04-1 DESCRIPTION: This procedure does not address the possibility of , regaining hea:

transfer in one SG.

DISCUSSION: Section III.C.2.9 of' the TBD states that, "If heat transfer 's  ;

occurring in only oua SG, then actions should' continue to attempt to restore heat transfer to the other SG, if possible."

E.04 makes no reference to :the situation where heat transfer "- )

i recovei ed in one SG. If SMJD's interpretation of recovering heat {

l transfer is to restore heat removal via any. SG, then this shoui i

be stated, Howeve r, in view of E.03 step 12.0, it does not appear- l l

that this is so. His step sends the op~erator to E.04 if heat transfer is lost in "Qna or b.cfA OTSGs." Al so, assuming the

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operator has lost heat transfer in anly one SG, per E.03 step 12, ,

and cannot regain it in E.04, then he is sent to CP.iO4 This procedure titled, " Transient Termination Following and Occurrence 1 1

That Leaves The RCS Being Cooled By HPI Co ol i ng ", 'is not l I

l applicable because one SG is removing heat. l SMUD should consider ad di ng guidance in E.04 to address the i

possibility of regaining heat transfer in one SG. Ia any event, SMJD should : correct the problem of sending the operator to an l

apparently inappropriate procedure, j 1

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, SECTION: ' E.04 Loss 'Of Heat Transfer 4 MAeER: E.04-2 DESCRIPTION: Starting a RCP per' step 12.2 ,

DISCUSSION: Re TBD discusses incresing RCS pressures ~ and pressurizer-level in this situation (TBD section IV.B.3.2). This is in anticipation '

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of subsequent : RC pres'sure and pressurizer level decreases caused l by collapse of hot leg voids. SMUD shoul:d consider adding this guidance either in the procedure or as an inforrution step.

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l SECTION: E.05 Excessive Heat Transfer MSSER: E.05-1 >

DESCRI N DN: Step 1.0 - Tripping Feed" Pumps DISQJSSION: Step 1.0 of this procedure states to " trip MFW and AFW pumps which j i

are still supplying flow to the OTSGs" when pressurizer level .is  !

't es s than 10" e either OTSG level increases to 95% e Tcold -

i decreases to 525F.

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Operating experience indicates that a 525F trip pofist for feed pumps is not always necessary. For . example, a weeping MSSV could I be causing a cooldown at a rate within limits. Though plant operators may not be able to stop the ove rcool ing, it may be- l i

desirable to feed the affected SG and allow the plant to cooldown I on the leak. These kinds of actions, stopping al1 feed, should be predicated hn rates of RC temperature change and other applicable limits. The present feed pump trip criteria do not provide adequate guidance for overcool ing transients that start at or l below 525F and should be revised to address this issue.

l A less than 10 inch pressurizer level feed pump trip point appears premature in the event that 'the operator has not taken prompt actions to contml ovemooling and pressurizer level. Data exists

.to show l ow pres s ur ize r level exc u rs ions post-trip caused by imp rope r bypass valve and/or safety valve operation. Per E.02

" Vital System Status Verification", excessive . primary to secondary heat tran sfe r is in existence when RCS pressure and temperature are decreasing with. SG pressure less than %0 psig and SG Tsat 51-1170856 00 t Page 19 of 31-

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HUMBER: E.05-1 Cont'd 3

l below 540F. Given that a bypass valve stuck open momentarily such j l

that SG Tsat is reduced to 540F, a pressurizer level deficit of l 210 inches could occur. Depending on when additional makeup is started and the magnitude of the cooldown, pressurizer level ntay go below 10 inches. In a situation such us this, P-T on the edge of the post-trip window, isolating the 1BV would be desirable over j 1

tripping the feedpump s. This is especially true since recent j l

overcooling transient data indicates draining the pressurizer with {

1 RCPs on will itkely not cause an irrrnediate loss of measured i l

subcooling margin. l 4

SMUD should consider develo ping less restrictive criteria than i

l only those utilized for press urizer level and Teo'id and should f ensure that prompt operator actions are taken to quickly mitigate l ove recol ings.

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SECTION: E.06 SGTR ESSER: E.06 DESCRIPTION: Selection of Emergency Cocidown Rate DISCUSSION: The TBD states that "the cooldown rate may be increased ' to e maximum of 240F/HR down to 500 F. TNT If8

a. the affected SG 1evel(s) is/are ' increasing. rapidly (several la rge tube leaks) and carr,f over could occur before 500F THOT at the normal cooldown rate QB

b. radiation release rates are _p rojected to reach the integrated TPACC limit (as defined in 3.4.1) before 500F THOT at the normal cooldown rate (again, several' large tube leaks would probably have to occur)"

It appears that SMUD has , attempted to adopt this guidance in E.06.

Step 10.6 states: "If the SGTR leak rate is greater than the 4

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capacity of one makeup pump OR the condenser is not available-

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i then use the emergency SGTR cooldown limits;" Depending on-plant conditions at the time the decis. ion to cooldown is made, SG 1evel (s ) may already be quite high. In sucbases tube ruptures within the capacity of one makeup ptrnp can rapidly fill a SG' to carry over l evel s. That is, if RC press ure is immediately J

reduced to a 50F SCM with RC ternperature equal to 555F, make up I pump capacity will be about 450 gal / min. (assuming WI valves are used, as i n stru cted , to maintain 100" pressurizer level per E.02 i step 7.2). SMUD should consider developing criteria that allows the operator to determine probability of overfill at 1.100F/hr for all possible initial conditions (e.g. , nomagraphs).

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IOSER: E.06-1 Cont'd  !

Relative to the condonser being unavailable, this will certainly i

increase . the of f site dose. Howeve r, this criterion for r ap t : -

cooldown, which was in ATOG, was dropped from the TBD. It was decided that a rapid cooldown was not warranted 'unless integratec doses would exceed predetermined limits . before the affected 5G could be is ol ated at 500F. Normally, condenser unavailability alone will not result in, doses greater than the TBD limits.

Conve rsel y, other complications could resuit in excessive doses even with the. condenser ava il abl e. SMUD , should consider-determining a source term (uc/cc) or other criterion above which rapid cooldown should be accomplished and delete the unavailable condenser c'riterion. ~

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SECTION: E.06 SGTR IU SER: E.06-2 DESCRIPTION: Procedure B.4, Section 6, Guidance To Maintain NC Cooldown While ]

Continuing With E.06.

DISQJSSION: Procedure B.4 Section 6, step 6.2 has the operator verify )

. conditions required for NC. They are:

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1. Verify Aux FWS auto start. l

2. Verify both OTSG 1evels approaching >50 pen:ent ~on tne Operate Range (approx.135" Startup Range).

3. Verify RCS equal to or greater than 50F subcooled and l RCS delta T is equal to or less than 100F.

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4. If the previous three steps cannot be ve rified, core j cooling must be provided by WI flow. Perform EOP Procedure E.02.

Step 4 is not enti rel y ' correct as written. With Aux feedwater flow est'ab l i sh ed , 50% on operate range is not required to adequately cool the core. Conversely, even with no intnediate auto start of AFL 50% on the operate range will provide NC, however, g not indef initel y. Therefore, these things alone- will not force PI Cooling based on the TdD symptomatic approach. Going to E.02 and checking symptoms is the correct thing to do. Conside r i

' changing 4 above to, "If the previous three steps cannot be verified, perform E0P procedure E.02. " Further, any mention of SCM should include reference to VSM if SPDS is available.

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9 SECTION: SGTR E.06 maeER: E.06-3 DESGtIPTION: Steaming A SG With A TR And Unisolable Steam Leak In The Reactor Building.

DIS (11SSION: E.06 appendix A step 2.0 should add a refe rence to steaming preferably to the condenser. Suggest the following:

2.0 If the steam leak is inside the reactor building, then steam the OTSG, pre fe rabl y to the condenser, only if......

Refer to TBD chapter III.E paragraph 3.8.b for guidance on this j point.

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4 SECTION: E.06 SGTR ESSER: E.06-4 DESGtIPTION: Actions to Mitigate RC pressure rise - when SG is filled and RC pressure is greater than lowest MSSV lift pressure.

DISQlSSION: Two cautions in E.06 refer to this situation. They state

1. Caution: An OTSG must not be allowed to fill if RCS pressure is greater than the code safeties setpotret of 1050.

2. Caution: If an OTSG is filled solid, RCS pressure must be h el d below 1,000 PSIG to prevent lifting code satwties.

The TBD states that if adequate SCM door- not exist, full HPI flow 1

from two WI pumps takes precedence even if a SG is filled solid l on tne secondary side. Also, it provides guidance on how to limit '

RC pressure increases d uring such a situation. Both of these  ;

\ i aspects should be addressed in the procedure at this point. I N

Even though most of these aspects are covered later in the procedure (step 18) they are presented relative to isolation of both SGs which requi res initiation of WI cooling. Presenting this guidance earlier outside of the context of HPI cooling can prevent confusing the operator. For example, if WI is on due to  !

TR, the operator may not realize that it is acceptable to reduce RC pressure, 'in an ef fort to prevent MSSV lifts, below the VSM line as long as two HPI pumps are on at full flor. It is recommended that guidance relative to this issue be placed in the procedure, perhaps as information, where the above stated cautions fi rst appear.

51-1170853 00 Page 25 of 31

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SECTION: E.06 SGTR

IGNSER: E.06-5 DESCRIPTION: Steaming of affacted OTSG.

DISCUSSION: Steps 16.1.3 '& 4 direct the operator to. steam the af fected OTSG to promote natural circulation and maintain the tube.to shell delta T less .than 100F, respect 1yely. Howeve r, If the SG has - been isolated per step 16.1.2, above, because its ' level was not below 955, then the TBD guidance is not to steam the affected SG. This TBD guidance is. found in Chapter III. E.3.4.3 as part of the bases for TRACC (Tube Rupture Alternate Control- Criteria). It states in part, This criterion (not steaming the affected SG) is intended to prevent carry-over in a steaming SG. Carry-over could damage the open steam valves (EVs or ADVs) and result in steam leaks."

SMJD should consider this' %D guidance as it relates to this step in the EOS.

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SECTION: ICC fnadequate Core Cooling '

m3eER: ICC-1 DESCRIPTION: WV Closure DISQlSSION: Information step 9.0 correctly states that the TVs should rema',

open until . the RCS is subcooled or until DHR is in operation wit-RCS pressure less than .140 PSIG. Step 27.0, however, would alic=

HPV closure at RC pressure less than,150 PSIG. Step. 27.0 shou' :

be written to be consistent with information step 9.0.

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1 SECTION: CP.101 A Large LOCA Has Occurred N CP.101-1 {

and the Core Flood Tank is Emptying.

DESCRIPTION: Step 2.0 DISCUSSION: The i n st ru ctions of step 2.0, including times given, are i

necessarily predicated upon one and onl y one failure type, (probably a D.E. shear of the CFT line).' If th'ere is a CFT line f ail ure it could be in a myriad of ways, any one of which will not follow the times and pressures stated in CP.101. Because of  !

I this it may not be clear whether a CFT line has failed or not; if a CFT line has failed it may not be clear which one. Further, CFT in st rumen t fail ures along with the other concoms stated here could cause the operator to isolate the. wrong LPI valve.

_ As a res ul't of these uncertainties, B&W has always advised the

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1 i Utilities to balance LPI flow to a plant specific value (1000 GPM for SMUD) per line. Should only one LPI pump be available, then i

the LPI punp dis' charge cross-tie is to be opened and flow adjusted to provide a minimium of 1000 gpm per injection line using one LPI pump. Achieving these minimium flow values per line ensures adequate ECCS flow even with a sheared CFT/LPI line. Th is is based on 10CFR50.46 "LOCA Anal ysis" and is what is reflected in 1BD and ATOG.

SMUD should consider deleting step 2.0 from the procedure. I 1

A further concern is operator burden. If the operator verifies 51-1170856 00 Page 28 of 31  ;

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'1 M3eER: CP.101-1 Cont'd 'l balanced flows the core will be adequately cooled; there' is no requirement to attempt to determine which CFT line, i f any, has q failed.

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1 SECTION: Rule 2 - CONTRG. HPI i MSSER: Rul e 2-1 ;

DESCRIPTION: TElWINATION OF HPI DISCUSSION: Refer to TBD Chapter IV.B.2. A.5. This part of the TBD discusses stopping WI flow. .

The SMJD E(P rule 2 part .1 interprets the TBD co',*rectly and has stated ' it almost verbatim. . Rule 2 part .2 however, as written requires a 100" pressurizer level. The 1BD does not require .a; y specific pressurizer level to stop WI flow. It . indicates that HPI flow should be stopped if the leak or contraction rate is within the capacity of the normal make up system and SCM is adequate. It fupther discusses establishing normal makeup.

It is suggested that, in Rule 2 part .2, SMUD delete the 100" pressurizer level requi rement and add that the RC leak or contraction rate be within ' the normal. makeup system capacity.

$ Further, SMUD should add a statenent in rule 2 ' part .2 to . ve rify start of normal makeup prior to stopping HPI.  !

d 51-1170856. 00 Page 30 of 31

SECTION: Rule 6 Reactor Vessel PTS Considerations MSSER: Rule 6-1 DESCRIPTION: PTS Limit (Rule 6)

DISCUSSION: Rule 6 step 1.1 states:

"RCS temperature dropped below 500F and. . . .. ."

SKl0 should consider adding the 'following (refer to . TBD Chapter IV.G.2.0) TBD words

". . . . . i f an y valid RC temperature. . . . ."

This should eliminate any confusion as . to whether to use Thot' Teold, I/C(s), or Tay,.

1 51-1170856 00 Pace 31 of 31

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SAD Resoonse to B&W " Review of SMUD's Emeraency Ooeratina Procedures" The following are SMUD's responses to the comments cotttained in the

" Review of SMUD's Emergency Operating Procedures" completed by B&H.

Each B & H comment is summarized and is followed by SMUD's response incleding the actions SMUD will take to resolve B&H's recommendations.

References are to the report " Rancho Seco E0P Technical Basis for E0P POM-248". The B & H review was based on a literal interpretation of the E0P's thur did not include operator' classroom / simulator training or adminis'trative procedures which instruct the operators how to implement the E0P's. This response evaluates the B & H recommendations in light of these other factors.

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B & H Recommendations:

Comment E.03-1: " Consider moving the actions of E.03 Step 6 to follow E.03 Step 3.2."

Response: This recommendation will be adopted and E.03 will be revised prior to startup. Refer to " Comparison of-TBD Fig. III.B-1 and E.03" Difference #5.

Comment E.03-2 Add information: " maintains at least 150 gpm AFH [

flow to each SG until loss of subcooling setpoint is j reached if incore T/Cs are not decreasing" to Step  !

3.4 on Information page E.03-2. Do not include i thermocouple response modifiers to AFH Flow.

Response: This information is contained in Rule 3 of the E0Ps. l SMUD operators are trained to have this information  !

committed to memory. In addition, the rules are located at the back of E0Ps and can easily be referenced at any time. It is, therefore, not

nccessary to place the detai?' on the information

< pages. The thermocouple mocifier will be retained

until the TBD change is finalized or other finalized

analysis shows it should be removed.

Comment E.03-3: "It is recommended that SMUD change CP.104 Step 7 to reflect these concerns. A possible change would be:

7.3 The RCS is saturated with SG(s) operable, and cooldown rate is less than 100F/hr, then go to Step 9.0."

} Response: CP.104 is being revised prior to startup to include

• the information described above.

I Comment E.04-1: " Consider adding guidance in E.04 to address the _

possibility of regaining heat transfer in one SG... l correct.the problem of sending the operator to an apparently inappropriate procedure."

Pesponse: Correction of the problem of sending the operator to an apparently inappropriate procedure will be dor.c 'l before startup and is addressed in the analysis of TBD III.B.2.8/3.5 Difference #1.

Consideration of adding guidance to E.04 for s~1ngular OTSG' heat transfer recovery will be done after startup because:

1) Operator Training emphasizes continued efforts to restore' inoperable equipment / systems.

2) The only identified apparent procedural problem will be corrected prior to startup.

3) The E0P symptom based approach for availability of heat transfer is successful if either OTSG is operable.

Comment E.04-2: Consider adding guidance to raise pressure and pressurizer level when starting an RCP per E.04, step 12.2.

i Response: Refer to analysis of TBD Chapter III.C.2.7/3.5, l Difference #1.

g Comment E.05-1: "The present criteria...do not provide adequate guidance for transients that start at or below 525".

"SMUD should consider formulating less restrictive l criteria."

Response: Step 1 of E.05, " Excessive Heat Transfer," will be revised, prior to startup, to address transients which start at or below 525 F.

The information page will also be changed to provide further clarification that tripping of feedpumps.is dependent upon a change in temperature if a transient occurs when the RCS is below normal operating temperatures.

In addition, the E0Ps will be modified to include a cooldown rate associated with the requirements to trip feedpumps for overcooling. Reference

" Comparison of TBD and E0P flowcharts TBD figure III.D-1" Difference #1.

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Comment'E.06-1: 1)- .SMUD should consider developing a criteria that allows the operator to determine the probability.

of overfill at 1100*F/hr.

2) SMUD should consider. determining a source term (pc/cc) or other criteria above which rapidL cooldown should be accomplished.

Response: 1) As-discussed in Comment.E.06-1,. tube ruptures. H within the capacity of one makeup pump (i.e., j f450 gal / min at 555'F) can rapidly fill a SG to- 1 carryover levels. To prevent this from '

occurring, the E0Ps will be. revised to . clarify the " greater than the capacity of the makeup.

pump" criteria by providing a specific gpm value j l

associated with normal makeup capacity. .

I This will prevent the SG overfill causedLby a j slow cooldown. rate ccncurrent with a high (450' gal / min) makeup rate. '

2) _The E0P's.will be revised to implement a criteria related to dose for.using rapid cooldown. Until these criteria are developed, q l the more ce ervative criteria based on '

condenser e allability will be retained.

Comment E.06-2: Consider changir.g B.4, Section' 6, Step 6.2 part 4, to: "If previous three steps cannot be verified, perform E0P Procedure E 02."

Response: Procedure B.4 is in revision to incorporate plant modifications and other startup commitments. . The revision draft of Rev. 41 to B.4 provides-the following direction' corresponding to Step 4.0 of the 1 B&W comment.

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j "6.4.5 1E the conditions required for natural circulation cannot be verified, JJiB go to E0P E.01 - Immediate Actions."

i This direction essentially incorporates- the i recommendations of this item since E.01'is the proper _i E0P entry procedure and evaluation for whether HPI j cooling is necessary will be done within the:EOPs. j Also, specific guidance for evaluating SCM is j provided within the E0Ps (E.02) at the appropriate ,

place.

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Comment E.06-3: E.06 Appendix A, Step 2.0, should reference that steaming to the condenser is preferable.

Response: E.06, Appendix 'A', Step 2.0 provides the direction recommended in TBD Section III.E.3.8.b. It does not specify steaming to the condenser, if available.

This action would be understood by the operators because of their training and understanding of the objectives in addressing a SGTR situation.

Comment E.06-4: Guidance on full HPI flow if SCM does not exist and on how to limit RC pressure increases during such a situation should be included in E.06. ,

k Response: The recommendation of this. item is to provide earlier direction for preventing lifting of the MSSVs "outside the context of HPI cooling" so as not to confuse the operator. Incorporation'of this recommendation is not justified for the following l reasons:

1) Prevention of MSSV lift receives strong emphasis throughout E.06. In addition to the Cautions .

mentioned in the B&W recommendation, there is a  !

Caution prior to Step 1 that addresses MSSV  !

lifting. Procedurally, the operator is directed to cool the RCS.to a point where OTSG isolation

\ can take place without MSSV lift. This )

direction is provided by Steps 10.0 and 15.0.

Both are before the Cautions referenced in the

$ B&W recommendation.

2) The B&W recommendation indicates that the required actions of TBD Section III.E.3.7 are tied to being on HPI cooling in E.06; however, the related step (19.0) does not address HPI cooling, only whether SCM is adequate. This procedure step is at a logical point in the overall flow and is in agreement with the recommended flowchart for a SGTR situation in J the TBD. j

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E.06-4: Response (Continued)

3) E.06, with its current direction for prevention  !'

of MSSV lift, has been used for numerous simulator training sessions. Never has there been any feedback from any operator that- a indicates there is a confusion issue on this  :!

aspect of the procedure. j l

Comment E.06-5: SMUD should consider the TBD III.E.3.4.3Lregarding 1 steaming an isolated 0TSG to reduce OTSG 1evel in i E.06 Step 16. i Response: This recommendation seems to be that due to'the sequencing of substeps in E.0 Step 16.0, .the operator may-steam an 0TSG previously isolated because of a j high level.. Step 16.2.1 directs the operator to. )

isolate an affected OTSG if its level reaches 95% and. 1 to attempt to lower level below 95% through the use of OTSG blowdown. In order to ensure.there is no .<

confusion, Step 15.0 (or its information page) will ,

be changed to emphasize that isolation of an OTSG for -l high level requires it to' remain isolated and further '

steaming / feeding for level control is prohitited.  !

Comment ICC-1: Information page for Step.9 is inconsistent with Step 27.0 regarding allowing HPV closure at pressure less than 150 psig.

i Response: E0P's will be revised prior to startup to resolve this discrepancy.

Comment CP.101-1: SMUD Should consider dropping Step 2.0 from the procedure.

Response: Step 2.0 of CP.101, regarding CFT line breaks, will 4 be removed to eliminate the additional operator burden of CFT status verification. In addition, Step.

I will be modified to include operator verification 4 of a LPI flow path to each injection nozzle in order l to insure adequate core cooling in the event of CFT line break.

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Comment Rule 6-1: Consider ' adding ". . .if any valid RC temperature. . ." i to-Step 1.1.  !

Response: The E0Ps will be revised prior..to startup'to. provide ]

guidance to usa the valid. temperatures referenced in <

TBD Chapter IV.G.2.0 l

Comment Rule 2-1: "The TBD does not require any specific pressurs level. l to stop HPI ' flow." "It is suggested that, in Rule 2,- .j Part 2, SMUD drop the 100" pressurizer.. level . j requirement and' add that the RC leak or contraction i rate'be within the normal makeup system capacity. 1 Further, they should' add a statement in Rule 2. Part: d 2, to verify start of normal makeup prior'to stopping' )

HPI."

n Response 1) SMUD makes a distinctionLbetween " Terminating-  :

HPI" (refers to stopping flow with the intention of not reestablishing'it) and " Throttling HPI" j (which may include _ reducing flow.to zero for; periods of time to avoid PTS etc.). reference - ci AP.23.06, Enclosure 8.3. ~ Rule-2, Part 3, allows HPI flow to be stopped-(i.e. throttled) anytime-SCM exists regardless of pressurizer level.

Thus, Rule 2 allows;HPI to'be stopped an6 started as necessary to control inventory.

2} CP.105, Step 4.2.2 in " Control HPI Flow" discusses establishing letdown and makeup. In addition, operator training ensures that normal makeup would be established to provide RCS  ;

l inventory control and RCP seal injection. It, therefore, is not necessary for this information to be included in Rule 2.

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ATTACHMENT 2 i

Emergency Operating Procedure Technical Basis j f

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