ML20155D165

Summary of 880922 Meeting W/Numarc Re Station Blackout Issues.Attendee List,Agenda & NUMARC 87-00 Seminar Questions & Answers Encl

ML20155D165
Person / Time
Issue date:	10/03/1988
From:	Tam P Office of Nuclear Reactor Regulation
To:	Office of Nuclear Reactor Regulation
References
REF-GTECI-A-44, REF-GTECI-AE, TASK-A-44, TASK-OR TAC-40577, NUDOCS 8810110105
Download: ML20155D165 (69)

Text

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CRCANIZATION: hUC'.rA ttANAGEM:NT AND RESOURCES COUNCIL (NUMARCi

SUBJECT:

MEETING SUFFARY. MEETING CN SEPTEPBER 22, 1988 CN STATION BLACK 0UT ISSUES (TAC 40577)

REFERENCE:

(1) Notice for September 22, 1988 Meeting, P.S. Tom to J.F. Stolz, dated Septerber it. 1988 (T) Peeting Surrary by P. Tan, Septerber 20,19P,8 (3) letter Transmitting Several Final traft NUVARC Docurrents, W.H. Rasin to NRR Dire. (or, Septeriber 20, 1988 The working meeting with NUPARC personnel was held as follow-up to a reeting held on Septa ber 15, 1900 (see reference (0)), and in accordance with reference (1). The purpose of the necting was to specifically provide staff ccreents on 144 responses provided by Nb ' ARC to utility questiens in varicus station blackout trainitg(sininars, and to corrent on final draf t docunents transnitted by reference 3).

NUMARC personnel verbally responded to 144 questions received from utility attendees during sevet al training sminars. The questions and /nswers (Cs and As) were transcribed and a slightly edited version was handed out to reeting attendees. NUP/RC personnel and the staff discussed these Cs ord At and results of the discussion were docurented as hard-written narkups (Erclosure 3).

NUPARC sun'litted a decurent 2ntitled "hlMARC 87-00 Errata Shttt for Industry".

This submittal (Enclosure 4) corrects er rors in the NUPARC report on station blackout.

By refererce M. NUPARC submitted its final diaft generic respcose to station blackout, ard its fir.al draft Appendix F to htPADC 07-00 and associated topical report. These final draf t docurrents were prepared based en discussions with the staff in the Septerter 15, 1908 neeting.

The staff irdicated that NUf'AFC nay proceed to sutrit these docurents in firtl form in the near future, and that NUf'IRC can espect a letter of appresal fron: the staff if the firal fotrs fully reflect agrecrents rade in the reeting.

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. is a copy of the attendee sign-in sheet. is the meeting agenda. No more future reetings were considered necessary.

Peter S. Tam, S nfor Project Manager Project Directorate I-4 Division of Reactor Projects I/I!

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Enclosures:

As stated See next page i

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4 Meeting With NUMARC On Station Blackout Issues September 22, 1988 Agenda Personnel Approximate tire Introduction of personnel P. Tam, NRC 9:00 - 9:10 Opening Statement F. Rosa, NRC 9:10 - 9:20 Opening Statement Russell Bell, NUMARC 9:20 - 9:30 Technical Discussion:

NUMARC NRC M. Childers P. Gill S. Floyd J. Knight J. Harnden C.Y. Liang S. Maloney J. Raval A. Marion F. Rosa et al.

J.M. McGarry et al.

• NRC Staff response to NUMARC 9:30 - 10:00 documents submitted on 9/20/88

• Discussion of questions raised by 10:00 - 1:00 participants in NUMARC seminars LUNCH 1:00 - 1:45

• Errata NUMARC-8700 1:45 - 3:30 NRC Staff Caucus (if needed) 3:30 - 4:00 Sunmary 4:00 - 4:15 Administrative matters 4:15 - 4:30 (date for next meeting etc.)

G e.In ue

_3 o 9 NUMARC 87-00 SEMINARS OUESTIONS AND ANSWERS Meets the 5fc 8

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GENERAL QUESTIONS 1.

Q:

Please explain the relationship between the NUMARC station blackout (SBO) Initiatives and the NRC's station blackout rule.

A:

Through our NUMARC Executives, Industry has committed to complett five SBO Initiatives.

Each plant should cenplete the staticn blackout Initiatives using NUMARC 87-00, whicn is Industry's guidance and

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methodology for completing the SB0 Initiatives, and is identified in the Staff's SBO Regulatory Guide (1.155) as providing guidance which is acceptable to the Staff for meeting the requirements of the SB0 rule (10 C.F.R. $50.63).

However, two areas addressed in *'.e Staff's Regulatory Guide are not covered by UUMARC 87-00 and should be addressed by each plant in accordance with the regulatory guidance:

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1.

Quality assurance requirements for SBO response equipment; and 2.

Consideration of technical specifications for SBO response equipment.

P Also, Sectiong.6oftheStaffRegulatoryGuide requires a system walk down and initial test for systems added to meet SBO recommendations.

This walk down requirement is not specifically addressed in NUMARC 87-00 but should be completed by each plant as appropriate.

2.

Q:

There are sever,al sections of the Reg.

ich do not match up to sections in NU 87-00.

Is comp ance with these sec ns necessary?

A:

The Staff m sev 1 errors in compiling the init Reg. Guide and ha sued a revised version ated August 1988 which corre, cts e errors.

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SECTION 1:

INTRODUCTION 3.

Q:

NUMARC SBO Initiative 5 requires plants not using alternate AC response to station blackout to assess their ability to cope for four hours, however, NUMARC 87-00 Section 7 recognizes a 2-hour category.

Must a 2-hour category plant assess coping for four hours?

A:

When Industry developed Initiative 5 it was not clear whether the required coping duration categories would f

include a 2-hour category.

Subsequently, the Staff revised the proposed rule and included 2-and 16-hour categories (which resulted in a revision to Initiative 1, c,alled Initiative lA).

NUMARC 87-00, a

Section 7.1.2 states that a 2-hour category pignt (pl, A) only needs to assess coping for a 2-hour duration.

Thus, Initiative 5 is satisfied for a l

2-hour category plant after assessing ability to cope fo.r two hours.

4.

Q:

Do plants need to verify the assumptions used in NUMARC 87-00 to develop the various methods and conclusions in the document?

A:

Yes.

NUMARC 87-00, Section 1.3, "Supporting Information" states:

-4_

Utilities are expected to ensure that the baseline assumptions are applicable to the plants.

Further, utilities are expected to ensure that analyses and related information are available for review.

Plants should consider whether their plant configurations, design and/or procedures conform with the NUMARC 87-00 assumptions.

These considerations and judgment should be documented and available for NRC review.

However, utilities are not expected to perform rigorous analyses or evaluationsg M vt..'fy.'a the e.u f' N d Ah>\\4 f.L-6'70 0 WECTIC 2

GENERAL CRITERIA AND_DASELINE ASSUMPTIONS 5.

Q:

To what extent will plants be required to verify the assumption regarding dominant areas of concern?

A:

Utilities must consider an area to be a dominant area of concern if it satisfies all three of the following criteria:

(a)

Contains equipment that is needed to function early in a station blackout (within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />) to remove decay heat; LI

(b)

Significant heat generation sources are present after AC power is lost and relative to the free air volume of the room; and (c)

Unless the operator takes action, the capability to remove heat is lost during a station blackout.

While the areas listed in Section 7 of NUMARC 87-00 are the areas that are most likely to be considered to be deminant ercas of concern, all plant areas meeting the above criteria must be analyzed.

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Qi When taking crc,dit for operator actions to apply

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supplemental cooling to a room within 30 minutes, is it necessary to perform a room heat up calculation J

for the full four hours oA only for 30 minutes?

A:

Section 7.2.4, which calculates the benefit of too%

providing supplemental cooling by opening doors, j

calculates an average steady state bulk air temperature for dominant areas of concern that is not time-dependent.

7.

Q:

If a plant has procedures that call for the operators to take actions during a station blackout and open I

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6-cabinet doors in the control room within 30 minutes, can they assume that the equipment will curvive a sta* ion blackout?

A:

If (1) the control room does not exceed 120 F, and (2) the operators take action within 30 minutes to open doors, it is expected that the temperaturn inside the cabinets will not exceed 120 F.

Control room components are assumed to operate properly in this environment.

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8. [

Q:

Is there a possibility that the RCP leakage rate may be revised in the future?

A:

Yes.

There is always a possibility.

However, the assumptions and bases noted in imMARC 87-0J, Section 2 5 cstabliqh a bounding leakaos ra}Ve of 25 gpm. ) < A w h k,

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, pam+%t *% nr S d O WW%Qf C P Amu-c &c.-ted by-th 3 ;'-((

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l rate assumption may need to be revised.

9.

Q:

In verifying the assumptions in NUMARC 87-00, and in completing the required assessments and analyses, must a plant assume a single failure of equipment or

. other assumptions normally considered for a design basis accident?

A:

No.

SBO is not a design basis accident.

Single failures of equipment and other assumptions normally considered for design basis accidents and analyses, need not be considered, unless the equipacnt would fail due to loss of the AC power caused by the SBO.

SECTION 3:

REOUIRED COPING D.MRATION CATEGORY 10.

Q:

Is the occurrence of switchyard-related events considered in determining the P category?

A:

The likelihood and duration of plant-centered events is reflected in the I 1/2 and I3 switchyard criteria.

3. 2.1 Of f-site _ Power Desiefn Chair!Lqt;_ eristic GIgng 1

Q:

In Part 1.A, how do you know if you "expect" to have a grid-related LOOP?

A:

As discussed on page 3-3 of NUMARC 87-00, only three sites have a grid-related LOOP frequency at the once in 20 year rate.

No other sites are expected to

. 4 exceed the once per 20 year grid-related LOOP frequency.

12.

Q:

Is there a discrepancy between Table 4 in Reg. Guide 1.155 and Tables 3-Sa and 3-5b in NUMARC 87-00 with respect to classification of P groups?

A: 2., tatic: 1-5a and ; St, :quare on 2 o..d Eon e suvuld--

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ria The Regulatory Guide would allow squares SW 3,

ESW 1 and 2 to be P1, however, this would be based on an SWR 1 category which the Staff has stated is not achievable.

As a result, it van appropriate to label these esquares "P2".

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13.

Q:

How do plants get credit for the asterisks in Tables 3-5b and 3-6b?

A:

If you are a hurricano exposed plant (identified by having analyzed a probable maximun hurricane (PMH) in your FSAR) you will get credit for the hurricane procedures if you fall into the boxes with the asterisks.

14.

Q:

NUMARC 87-00 Tables 3-Sb, 3-6b and 3-8 include asterisks which denote site upgrade attributable to implementation of plant-specific pre-hurricane shutdown requirements and procedures.

Why doesn't the Staff Regulatory Guide also include similar asterisks for their corresponding tabla?

A:

The Staff's Regulatory Guide does not specifically

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recognize p' ant-specific pre-hurricane shutdown procedures, and their corresponding value to plant-specific SDO risk reduction.

However, the Staff's Table 1 (Regulatory Guide 1.155, page 1.155-8) references NUMARC 87-00, Section 3 as being equivalent and, acceptable guidance to Regulatory Guide, Section 3.1.

r 15 Q:

can a utility use its own sno*> data covering the last 30 years?

At A utility always has the option of using site-t specific data.

1 Q:

Do plants in coastal areas have to use Tables 3-5b and 3-6b?

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. A:

No.

However, if your plant falls into a category with an asterisk in the proper box, you may want to consider the benefit of using the tables.

17.

Q:

By developing pre-hurricane shutdown procedures, does a plant reduce the risk of a hurricane-induced station blackout?

A:

Yes.

18.

Q:

In determining a plant's Offsite Power Design Characteristic Group (P-Group), can a plant use weather data other than that provided in the NUMAR'C 4

87-00 tables?

d A:

Plants may use plant-specific weather data as available.

The data provided in NUMARC 87-00 Tables 3-2 and 3-3 has been reviewed and accepted by the Staff and is provided to facilitate completion of the l

SBO Initiatives.

However, use of plant-specific data l

which differs from that provided is acceptable, subject to Staff review.

i 19.

Q:

Can sites which may be considered susceptible to salt i

spray take credit for switchyard spray down systems?

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Yes.

A switchyard salt spray down system, which reduces or eliminates the effects of salt spray, Ma[

justif use of zero for the "C" factor in Section MMk 3.2.ly t

20 Q:

To what degree will independence be required in order to be classified an I-1 category plant in Table 5 criteria 2B of Reg. Guide 1.1557 Must IEEE-765 be met in order to comply with Reg. Guide 1.155?

A!

IEEE-765 is a reference in both Regulatory Guide 1.155 and NUMARC 87-00.

However, 'lable 0, category 2b identifies the specific criteria to be followed which is consis, tent with the definitions of ptuferred and alternate power sourcos found in Appendices A and B of the NUMARC 87-00 d0cument.

M 21 Q:

If my FSAR has e 100-year return storm of 124 mph or less, does this mean that my ESW category is a 17 A

No.

All this means is you are definitely not an ESW 5 plant.

If you want to show lower than an ESW 4 category, further statistical treatment of plant-specific data is necessary, s g,dL Tak r 4.4. /.mr,,A+'JL7E %

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22.

Q:

How should a plant determine whether 12.5 or 72.3 is appropriate for use as the "b"

factor in the equation for determining frequency of loss of offsite power due to severe weather?

A:

While specific criteria were not discussed with the Staff, it was agreed that a plant would be justified in using 12.5 as the "b"

factor if the transmission lines were separated by at least one-quarter of a i

mile commencing at a point one mile from the plant.

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Plants may rely on alternate criteria to justify use of the 12.5 "b"

factor but the criteria may be subject to Staff review.

l 23./

Q:

How should the frequency of loss of off-site power L/

due to severe weather be determined for plants susceptible to salt spray?

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A:

The annual frequency of salt spray already considered f

l the effect of storns.

Thus, the annual expectation of storms should be entered either as h3 or as h4 l

j depending on whether the site is susceptible to salt i

spray.

The increased significance of salt spray is accounted for by its much larger multiplier (0.78 1

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compared with 0.012) in the equation predicting loss i

1 of off-site power.

Hencu, if a site determines that l

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it is susceptible to salt spray, they should enter the annual expectation of storms with wind velocities between 75 and 124 mph as h4 and zuro a, h3 in the equation shown in Part 1C section 3 of NUMARC 87-00.

l 3.2.2 EAC Power Conficurati2D t

.I 24.f/' Q:

Define emergency AC.

V G%e.gucy A C L5 A

fjstandby AC power supplies as defined in

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NUMARC 87-00 to meet GDC-17.

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2 5.,e' Q:

Ifasitehastwounits,both1/p,isthereany J

argument for go,ing to 2/4 at that site?

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A:

The 2/4 configuration is for diesels which are l

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normally shared between the units.

If the diesels l

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are not normally shared, there is no basis for using i

the 2/4 configuration.

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b 26.

Q:

When determining the number of necessary EAC standby I

power supplies, what load requirements should be f

j considered?

E A:

As described in NUMARC 87-00, Section 3.2.2 part 2.B, 1

I the safe shutdown loads associated with loss of I

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offsite AC power are the minimum loads which should be considered when determining the number of necessary EAC sources.

These loads do not necessarily include LOCA loads.

27.

Q:

Can a plant depart from existing procedures in order to natisfactorily respond to a station blackout?

A 10 C.F.R. 50.54(x) allows a plant to bypass l

procedures, if necessary, to respond to an emergency situation.

Compensatory measures should be taken to the degree foreseeable and practicable.

For example, l

l loss of ventilation concerns may require doors to be l

kept open in a,vitcl area otherwise required by i

l procedures to be secura.

20. #

Q:

Can an Alternate AC (AAC) power source be considered V

in the determination of available EAC standby power supplies?

At No.

An AAC power source cannot be counted toward the available EAC determination and be considered as AAC at the same unit.

29.

Q:

On page 10 of Reg. Guide 1.155, should the last line b'

of footnote C read "at each unit" rather than "at all units"?

4 l

A:

No.

The footnote is correct, and this is made clear

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in the NUMARC 87-00 document.

See, NUMARC 87-00, pp.

3-15, 3-16 which makes a distinction between multiple and single-unit sites.

1 30.

Q:

If I am an EAC Group A, and I have a non-1E diesel G

1 which could be used as alternate AC, do I have to use r

AAC?

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A:

No.

As long as,you are in tho 4-hour category or I

less, or take thu necessary actionr. to get into that l

i category, the:4 ycu can either perform the NUMARC j

87-00 Section 7 coping assessment or use an AAC 3

f source.

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i 31.

Q:

In Appendix C, AAC configuration 2B, how many EAC J

l sources are available?

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A There are two normally dedicated diesels per unit which would put you in EAC Group C for each unit.

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Thecross-tiesfrovideganAACoptionbutdonot g

change the original EAC configuration.

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3.2.3 EDG Reliability 32 /

(:

What is the distinction between target reliability and actual reliability?

How is monitoring done?

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A:

Tha v 'v' terg:t reliabilitier e -

OO r p 5A L to M J4.u k L; in ;,"Ji'. ARC 07

~ xw Otione 3.2.3 and 0.2.4 are u;ed in ;;rt * %w. 4 M N

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Once thekcoping duration, with tar et reliabilities, is established then utilities will i

maintain these reliabilities through a program i

discussed in Appendix D of the NUMARC 87-00 document.

This program is curren*.ly under further development

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by NUMARC as repolution to Generie. Issue B-56, Detailed criteria for calculating actual reliability and maintaining performance to sustain the target reliabilities will be part of the EDG Rollability

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Program.

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Q:

What happens if a plant uses.975 reliability in order to get itself into the 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> category, then I

later falls below this level?

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r At The ptoces aintainin e target relladilit h WM 4/Q g<

Will be datailed in the EDG Reliability Program h

I, developed as resolution to Generic Issue B-56.

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34.

Q:

Is the INPO definition of how to monitor EDG failures and starts on demand consistent with the NSAC-108 definition?

4 A:

Yes.

It is our understanding that criteria for determining successful starts are consistent with l

NSAC-108 definitions.

35 Should we be complying with NS 087 A:

The deta of t EDG Reliability Program are currently e - evelopment and will be factored into the r olution of Ge ic Issue B-56.

This is J

cheduled for c,ompletion by end of this year.

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36.

Q:

If I am using an AAC source can I pick an EDG target reliability of 0.95 instead of.975?

j 4 M M GA C. If D hI ff Y[AslongastheAACsourcecanachieveand A:

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maintain safe shutdown for the longer duration that j

might result from using an EDG target of.95 instead of.975.

37.

Qt Two diesels (one normal and one altarnate) are l

available to each safe shutdown bus.

How is unit average EDG reliability determined?

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A:

If both diesel are required per your licensing basis, average the two diesels for each bus and then average the bus reliability to determine unit average EDG reliability.

one diesel is required If only % { % lb M =:per

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4 -* sver cr.; 01.. 1 per i

hus The' other diedel may qualify ad an AAC source.

J 38.

Q:

If I am using one of my existing Class 1E machines as

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an AAC source, how do I treat it in averaging EDG reliabilities?

A:

It would still be avt. raged in with the other Class 1E diesels for that unit's SBO evaluation.

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39. /:

Q If we have. fewer than 50 domands on our diesoin, then we can only use one of the three criteria, is that correct?

I A:

As noted in NUMARC 87-00, Sectior. 3.2.4, any of the evaluation criteria are acceptable with EAC Grouping A,

B or C to establish the 0.95 or 0.975 target reliability.

The evaluation criteria is derived from the number of demands established as an indicator of past EDG performance.

As such, it is possible that fewer than 50 demands may be the historical indicator, but if start-up testing is included in the 1

__m_ _ _. _ _... _ _,.. -, - _. - _... _.. _ _ _ _. _, _. -. _ _ _ _ _ _ _. _ _ _. _ _ _,. _.. _.. _. _

demand sample then the number of demands could be increased.

3.2.5 Determine Conina Duration Catecoty 40.

Qt NUMARC 87-00 Table 3-8 indicates that a P1 - EAC group D plant would be considered as a 4-hour plant if the diesel generator (DG) target reliability is

.975.

What happens if you cannot meet the criteria for selecting the.975 target reliability?

A:

EAC group D plants are required to use the.975 DG target reliability.

If the plant's DG's fail to qualify for thip target, in accordance with NUMARC 87-00, Section 3.2.4, then ~he plant must increase c

the required coping duration to the next highest category (q2ga, fIom 4-huur to 8-hour).

3.2.6 Recuired_ Action 41.

Q:

Is the implementation of hurricane guidelines another way to comply with NUMARC Initiative 1?

A:

Yes, but only for those plants that fall into one of the asterisked boxes in Tables 3-5b and 3-6b.

l

42.

Q:

If we have.95 reliability based on past experience but can meet the criteria for selecting the.975 target can we do so and move to a lower coping category?

i As Yes.

But be cautioned that under the resolution of Generic Issue B-56 you will likely have to 4

demonstrate that you can achieve and maintain the higher target.

?

SECTION 4 STATION BLACROUT RESPONSE PROCEDURES 4,2.1 Station Blackout Reppense Guidelines 1

42.

Q:

Under NUMARC 87-00 Section 4.2.2(4), are plants required to have portable AC generators available as 4

a backup power source?

t At No.

Sectjon 4.4.2(4) states that portablo AC generators should be designated as backup sources 11 available.

There is no need to purchase one.

However, if such a source is going to be relied upon for coping purposes, procedures must be in place regarding its availability to be brought onto the site and used.

i 44.

Q:

Is it required for a BWR to exhaust the CST before switching to the suppression pool?

A:

No.

A utility can determine the order in which water sources are used as long as they are defined procedurally.

45.

Q:

Do we need to perform a study to identify safe shutdown instrumentation?

~

s A:

A study is probably not needed since such a list was required for Appendix R.

Also the EOPs should already identify the instrumentation being used to achieve and maiptain safe shutdown.

1 46.

Q:

Can credit be taken for diesels that have dedicated w) h m

eup capability?

j A:

Yes.

Using the AC-independent approach, dedicated l

makeup capability may be relied upon if the diesel l

i does not normally provide power to the essential and i

non-essential power supplies (see the definition of i

i station blackout).

The support systems for such I

diesels must also be independent of these power supplier, in order to credit their operation in a f

1 station blackout.

In order for the dienel to be

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l

,,.w-

e t credited as an AAC machine it must also meet the criteria set forth in Appendix B of NUMARC 87-00.

47.

Q:

Do you have to open all control room cabinet doors?

A:

No.

Only those that contain equipment being relied I

upon in a station blackout.

l 4

48.

Q:

How should procedures treat a situation where l

necessary instrumentation readings are lost in a l

t i

station blackout?

1 1

A:

Those instrument indications that are necessary for the operator to, cope with the blackout must be available during the blackout.

Should normal I

instrumentation be lost, procedures should direct the i

operators to utilize alternative instrumentation that 1

has reasonable assurance of operability during a r

blackout.

I l

49.

Q:

Are you recommending that we create a station j

i blackout procedure or nodify existing procedures?

i

[

l At That is up to each plant to 6ecide.

Some plants may

[

find it easier to write a separate procedure while l

I others may be able to augment existing procedures.

I i

F

- 23 _

50.

Q:

When drafting or reviewing station blackout response r

procedures shot 1 a plant assume that AAC is e

available?

A:

If a plant is utilizing an AAC source which meets all the requirements of NUMARC 87-00, Appendix B, then 4

the plant's response procedures should utilize that sourCG.

51.

Q:

When heat tracing is mentioned, does this include CST tracing?

l A:

Yes, if you are using the CST for a water source and it requires tra,cing to prevent freezing in the l

Winter.

4.2.2 AC Power Restoration I

.i l

52.

Q:

After power

,s restored does a utility have to L/

justify the continued operability of the equipment

{

located in the dominant areas of concern?

i At No.

Since analysis of the effects of loss of ventilation (see revised Appendix F) indicate no j

significant thermally-induced erosion ci' component

~.

reliability during the coping period, no degradation upon power restoration need be considered.

4.2.3 Severe Weather Guidelingg i

t J

53.

Q:

Do all plants have to meet the hurricane guidelines of Section 4.2.3 and do these guidelines qualify for the asterisks on Table 3-87 6

A:

Plants which have evaluated a probable maximum r

hurricane "1d use the guidelines in Section 4.2.3.

Plants which meet these guidelines do satisfy the asterisks on Table 3-8.

l b

[

54.

- Q:

Does ITUMARC 87-00 require plants to have procedures te shut down the plant two hours before a hurricane?

i Al If you have evaluated a probable maximum hurricane during plant licensing, then you should specify a I

site-specific indicator which would ensure that the plant would be in safe chutdown two hours before the i

j anticipated hurricane arrival at the site.

i C

h

j SECTION 7:

COPING WITH A STATION BLACROUT EVENT t

J l

55 Q:

What systems are required to cope with a station blackout?

At All systems necessary to achieve and maintain safe shutdown.

P 7.1.1 Cooina Methods

[ ] s'

~

1MP Q:

If an 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> plant uses Alternate AC, how much condensate inventory is required?

L 1

A:

Since the plant,is in an 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> category, 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> of l

condensate would be required to remove decay heat.

Ill L

i j

4ML Q:

How much compressed air is required?

At The amount necessary to operate valves for the required coping duration unless they can be manually i

i operated.

AAC plants would need a 1-hour supply

[

-)k

(

--- 'he air compressor is placed on the AAC cource r

l l

within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, unless the valves can be manually

?

j operated.

i i

i l

i l

r

, \\

Q:

Does the implementation of Initiative 1A mean that the requirements for condensate inventory, fuel in the day tank, etc., need not be considered for greater than 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />?

t&Y

_1

_n ' >

g y

/y'fesources }are: required; fy*1"'n

• "*"**W -

^*

""'tc 1

g r plants using the alternate AC approach, sufficient resources and capability must be provided to achieve and maintain safe shutdown for the duration of the current required coping time (12g2, 2,

4, 8 or 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br />, as anpropriate).

i 59 Q:

Must AAC power,the loads for all five items in

~

Section 7.17 1

l j

A:

The AAC machine must power all the shutdown loads i

necessary for coping with a station blackout.

l Therefore, at a minimum, the AAC source must power the loads related to the five topics in Section 7.1 l

4 that would normally be powered off of the EAC power source, except for HVAC as detailed in question number sixty.

The utility should determine if any l

other systems are needed to achieve and maintain safe shutdown and appropriate containment integrity, and I

l I

I

O supply power to these associated loads from the AAC source.

60.

Q:

Is AAC required to pover HVAC loads in the dominant areas of concern?

l At While the NRC has stated that they prefer AAC to power HVAC in all dominant areas of concern, there is a reccgnition that an AAC power source may not be able to power HVAC in all dominant areas.

If HVAC is not powered by AAC for a dominant area of concern then the AAC power source is acceptable as long as 4

the lack of HVAC is considered in the loss of ventilation ass,essment pursuant to NUMARC 87-00, Section 7.2.4.

61.

Q:

Can an AC power source be used to assist a plant that Q/ '

i i

chooses the AC-independent approach in providing

)

l coping capability'.

i 3

At Yes.

Additional AC sources can be used by AC-1 j

independent plants to assist in meeting their coping i

i requirements.

These power sources and support systems must be independent of the essential and non-i essential AC power buses.

j i

l

28 -

62.

Q Should Mark III plants provide a power source for hydrogen igniters?

At No, hydrogen ignitors are not required coping equipment because it is the intent of the rule to ensure that there wjll be no core uncovery and, consequently, no generation of hydrogen as a result of zirconium-wat re etions. bM

/* M '1 NC T

sYS~N WO un i

n 63.

Q:

If a plant can show that it can cope for four hours, must it use Alternate Ac?

At No.

Plants in a four hour category must either show that they can c, ope for four hours, or show that they have AAC available within one hour.

7.1.2 Conino Duration c4., ' Q If your AAC source is available within two minutes do you still have to have procedures to cope for one hour?

At No.

If AAC is available within 10 minutes as discucsed in Section 7.1.2, no coping assessment is necessary other than to verify that sufficient water is available to remove decay heat for the required

l

' py ( f u QA Nb C E duration nd that the baseline assumptions in NUMARC i

87-00 are applicable.

General procedure revisions in accordance with NUMARC 87-00, Section 4, are i

required, d *f d C-65.

Q:

If you use AAC, do you copg only for the time l

I\\

j required to tie in the AAC source?

i

)

A No.

If your AAC source is available within 10

% %%%v4

• g * (. y s y

j minutes, no coping assessmen is necessary If the AAC source is available between 10 minutes and one I

M AC-Y Y W hour, 49. eur copint; assessment must be performed for the 9.w-2tr:gourinterval.

i

]

66.

Q:

Section 7.1.2 says the 10 minutes for AAC not requiring a coping assessment is from the onset of a l

station blackout.

What is meant by that statement l'

given that the EOPs are supposed to be followed and 1

l have numerous required actions before the decision to i

i use AAC is even considered?

Most, if not all, of the 10 minutes would be used up following EOPs.

)

I At The 10 minute requirement was meant to cover the J

period between when the operators realized a station j

blackout had occurred and the AAC source was started i

i from the control room.

Therefore, oparators would 1

l

i perform the immediate steps in the EOPs to verify scram, primary system parameters, etc., and attempt to restore offsite power and start the EDGs from the control room per the EOPs.

When actions from the control room are upsu cessful in restoring offsite

.4 gX ef '.

,i -

Yr an onsite emergency AC power, h station Y blackout has been verified, ther *'e 10

-4="*=

eleek e If you can start and be ruady to load the I

E AAC source within the 10 minutes, taking all actions

[

from within the control room, the 10 minute criteria is met.

i

]

67.

Qt Section 7.2.1 of NUMARC 87-00 states that I

1 j

after one hour,,an AAC source may be used to provido q

r power to pumps and valves if the equipment is powered

[

from the AAC source."

Does this mean that credit cannot be taken for use of the AAC source until one hour into the event?

s A:

Yes, unless the AC source is available within 10 minutes from the control room, credit cannot be I

taken.

However, you can use AAC whenever available.

i i

l l

1 i

1 i

[

t l

I

• I t

2 2.1 Condensate Inventory i

L 68.

Q:

If a plant has a condensate storage tank with a k

capacity which exceeds its technical specifications, will the NRC recognize this additional capacity?

i

)

A:

It is expected that credit will be given for CST l

inventory in excess of technical specifications g

limits providec: this excess is controlled by w

l administrative procedures, km.g 4 Mhd l

)

% 2x s M,4[.

@(,

Mu AR C 3

1 V

69 Q:

Has the' Staff specifically said that it is acceptable i

n# a I to assume the technical specification numbers for S Cd

[

" - leakage, rate?

1 A:

Yes.

See, NUMARC 67-00, Section 2.5.

[

J l

70.

Q:

Do we have to consider primary system' makeup s

t capability?

l h

I At Section 2 assumes a reactor coolant pump seal leakage rate of 25 gpm with no core uncovery during a 4-hour j

i blackout.

Plants in a longer category using AAC nay l

J r

j need to power a charging pump for seal inj2ction or i

assess that core uncovery will not result from the l

F 3

longer duration.

1 i

l t

6 t

1 t

. i 71.

Q:

Given a procedural requirement during a station blackout to depressurize the RCS by initiating a maximum rate cooldown in order to reduce RCP seal leakage rate, can we take credit for this reduced l

leakage rate or do we have to assume 25 gpm per pump?

1 At The 25 gpm is the maximum allowed leakage r assumption.

_ _p wer l

leakage rates may be j t

4S stification may be based, in part, on system depressurization. M 72.

Q:

Can steam generator inventory be used as a source of water?

f A:

Yes, as long as you have the capability to j

recirculate this source.

l 7.2.2 Class 1E Battery Capacity 1

73.

Q:

Are plants which use the AAC option required to power a battery charger?

l At Yes.

3 i

l.

74.

Q:

If a 4-hour plant has a 3-hour battery, can the j

battery capacity be extended by providing the capability to charge?

1 A:

Yes, provided the source powering the battery charger f

is independent of preferred and onsite class lE

power, i

i Cancreditbetakenforalternafag u tiple battery 75.

Q:

channels or cross-connecting a non-safety station l

battery into its DC system to provide the additional capacity required to cope?

)

At Yes.

Provided, appropriate electrical isolation r

features and procedures are utilized.

i i

1 t

{

76.

Q:

Does load-stripping need to be performed from the I

)

control room?

I, 1

At No.

etace

,oad-stripping will nog,gccur until 30 f

/,.t m.4.al. sw ^" f"

• /roulf 2

s kroceduresjpeurspecify minutes into the blackout n eesenry

{

0::::

- --i actions.

I i'

77.

Q:

Is battery aging to be taken into consideration?

I L

J 1

l t

i

A:

Aging effects are already included in computing battery capacity in IEEE-STD-485.

78.

Q:

Is load stripping necessary?

At No.

If you can show the ability to cope for two or four hours without load stripping, then it is not s.. g (6 )

M W ID SW/

"- troquirg M n t @: ; :i' r necessary.ASection4'0 a m eh i d e n t i f y [t =M' idt9i. loads r ' W^ _,--s %

'"-C i.htt~d "U

'i g

T-4 i' it

<vt

_ -e4 A g ;d Upt OM blacke n ma g2astsicr.ger

..er.

appe cu e

$h f4 5 s

~1 % rh,, b ( hw,

J er -a w s.. - -2 r " _ g _ _ y _n

kg_,

/

r 7

Q:

Is hydrogen accumulation in batteries a concern, particularly wh,en using an AAC source?

At Hydrogen generation typically occurs during charging.

For the AC-independent coping method, only discharging of batteries would occur and hydrogen accumulation is not expected.

For the AAC approach, ene mlled b" HVA Q dd

=hyhp.. accumul: tier cheuld ha

}

2

-- A <r,} & Q

}Cla,A,4%

80.

Q:

What are the minimum DC loads?

A:

The DC loads required to achieve and maintain safe shutdown.

The minimam normal safe shutdown loads are all that are required to be fed from the DC source.

s 35 -

7.2.3 Comolessed Air 81.

Q:

What are the requirements for identifying the positions of valves in remote locations?

A.

The operator must have a positive means of identifying the positions of valves either locally or from the control room.

The only restriction is that the indication must be independent of the preferred and standby power sources.

Otherwise, any means of i

f J

indication is acceptable.

4 I

I 82.

Q:

What is the minimum required size of the back-up i

compressed air,acettmulators?

t t

I A:

If relied upon for coping, air accumulators must be

)

sufficiently large to allow the valves to operate for the number of cycles that they are expected to go i

l.

through in the course of the coping duration, unless i

the valves can be manually operated.

1 i

I l

7.2.4 Effects of Loss of Ventilation i

f 83.

Q:

Is the control room a dominant area of concern?

L I

h i

l t

i I

1 1

e i

i

-e

,-..---_-.--,.,,7----.,-m____._

_-_.-_--__._..~..m_

A:

It is assumed that the control room temperature will 0

not rise above 120 F during a 4-hour blackout; it is not a dominant area of concernk"y (ki'It'( m consequently fo opuaiors f*4e,actim to ofen iasti w e d en braet dus pm h su This assumption, should be assessed, and if it is 4, t. l (fo )

o( Ab%dAC-found that the assumption is not applicable, then the

fygg, control room would be a dominant area of concern for that plant.

84.

Q:

Does a coping analysie have to consider RCP leakage coincident with loss of HVAC?

A:

The coping analysis is limited to the items in Section 7 of NUMARC 87-00.

Temperature effects inside containm,ent are addressed in NUMARC 87-00, Section 2.7.1, and do not need further evaluation.

85.

Q:

Why is the main steam tunnel a dominant area of concern?

What equipment in the steam tunnel is important to safe shutdown and will it actually be affected by the teaperatures reached in the steam tunnel?

A:

Temperature sensors for detecting high energy line breaks are located in the main steam tunnel.

In a station blackout, bulk air temperatures may rise to a level that could trip the RCIC turbine.

s

. 0 86.

Q:

What assumptions apply to the area on the other side of a door that may be considered for providing supplementary ventilation?

A To take credit for opening doors during a station blackout, the adjacent area must be sufficiently large to maintain a relatively constant temperature when considering the additional heat loads imparted to the room from the dominant area of concern.

In addition, the adjacent room's bulk air temperature should not exceed the initial wall temperature in the dominant area of concern [ h k M 2 h A P J 51 M %M

• I%.

87.

Q:

What is the assumed location of doors?

i NQ eW -

6hM M\\/

d N

j

/

A:

-eor., s > src ;;;=:d te 5: locaiwd 4..

th; walir at f l e e -~

.f.,

M '\\g

,;I <p'. s $dh 9 L-%,

r n

l 88.

Q:

When doors are opened in a station blackout, is it I

appropriate to postulate the presence of a fire?

L

{

A:

No.

No other accidents need be postulated coincident with a station blackout.

This is consistent with the SBO rule.

i

't i

i l

i e

t 30 -

89.

Q:

Can credit be taken for HVAC penetrations to provide supplemental cooling?

Any sort of opening can be taken credit for as a A

I source of supplemental ventilation.

Howaver, to use the correlations in Section 7, the opening must adheretothesamgps,sumptionsasthoseappliedto

($g N

N^

w ** V doorsg e==8 4A A M.

90.

Q:

Can supplemental HVAC be provided through the use of fans powered by portable generators?

A:

The use of portable fens as a means of providing supplemental copling is acceptable when considering the AC independent method of coping.

I 91.

Q:

What heat loads need to be considered when performing the loss of ventilations analysis in Section 1R 7 2 T [

i A:

Heat generating equipment that is required to operate 3

i under station blackout conditions and all het surfaces need to be considered.

t 92 Q:

How do you handle the heat generation term for

{

insulated pipes in performing the loss of ventilation l

analysis in NUMARC 87-00?

t I

l

\\

\\

r

i

- l t

As A reasonable surface temperature must be considered l

for T, for insulated pipes.

Generally, the amount of insulation that is applied is specified so as not to exceed a desired maximum surface temperature.

This desired temperature would be a reasonable assumption for the initial surface temperature.

93 Q:

Can the openings in the floor and ceilings and the additional surface area due to a floor be included when applying the correlations in Section 7 of NUMARC 87-007 At The correlations of Section 7 of NUMARC 87-00 do not include floor s,urface area or openings in horizontal surfaces.

The purpose of these correlations are to allow the plant engineer the ability to easily perform a simple bounding analysis that will model the actual conditions.

94.

Q:

Is a utility required to analyze all areas in the plant to determine the additional dominant areas of concern?

A:

Utilities are expected to consider whether additional dominant areas of concern exist, utilizing the

i. l criteria set forth in NUMARC 87-00, Section 7.2.4 (p.

7-18).

95.

Q:

Why isn't the battery room a dominant area of concern?

A In general, battery rooms do not possess significant heat loads.

However, there may be a few battery l

rooms that are dominant areas of concern and they

)

would have to be addressed on a plant-specific basis.

N l

'9 6.

Q:

Was there a discussion with the Staff on the average

)

drywell temperature rise?

I A

Average drywell temp rature in a SS is bounded by I

4l%

M.<Aovt,

w the GE high energy ne break analysisf Plants which relied upon the GE HELB analysis or a plant-specific analysis which bounds the GEganalysis, need not l

address the drywell temperature effects.

97.

Q:

Is defeating secondary containment allewed for purposes of opening doors to provide supplemental cooling?

l 3

At Yes.

l l

l l

L

41 -

98.

Q:

Must you assume that a station blackout could occur at 3:00 a.m. when staffing levels are at a minimum?

I As Yes.

The blackout could occur anytime in a 24-hour l

period.

Therefore, any manual actions called for i

i i

)

must be capable of being performed by the minimum number of personnel that may be present.

4 4

i

• 99.

Q:

Is the utility required to use the initial wall l

(

temperature of 40 C in calculating the bulk air 0

I l

temperature?

I t

)

At The value of 40"c was used as a reasonable upper bound.

A plant,can justify a lower temperature based l

on plan expariance or measurement.

(

h i

r 7.2.5 Containment Isolation 1

100 Q:

What is the difference between steps 2 and 3 on page l

1 7-21 of NUMARC 87-00?

{

l r

I l

A Stap 2 covers valves which are being cycled to j

i, maintain safe shutdown whereas step 3 covers valves f

f I

which are not being cycled but may need to be closed

{

l to achieve containment integrity.

{

a l

1 l

l i

(

[

i

--,.-,,-.,,.--.,.-,._---t.---,-~--.

-,. J

101.

Q:

Can we assume that if our procedures call for valves to be closed they can be considered locked closed per Section 7.2.5, step 1?

A No.

Locked closed means a mechanical device of some sort has been applied to the valve.

Procedures calling for valve closure or administrative tagnuts do not qualify as providing locked closed status.

102.

Q:

Do you have to show that you can close both the inboard and outboard containment isolation valves?

A:

No.

Since you do not have to assume a single failure in addition to,the failures resulting in a station blackout, providing the capability to close one valve 1

would establish containment integrity.

103.

Q:

Is it a requirement to establish containment I

t/#

isolation if a station blackout occurs?

A No.

You need only establish contninment integrity if core damage is imminent.

104 Q:

Do we need procedures to close the valves?

l l

q i I

At NUMARC 87 00 does not specifically address this.

i 4M dt However, actions of this nature.mpefnortaally t

j proceduralized.

i i

i t

A223NDIE At DEFINITIQMg 1

105.

Q:

How does the NUMARC 87-00 definition of station blackout compare with that found in Reg. Guide 1.1557

)

1 l

At They are identical, i

l 106.

Q:

In a station blackout, are all the diesels at a unit i

l assumed to l' ail?

i 4

A:

Not necessarily.

The definition of station blackout I

states, in part, that "(ajt single unit sites, any i

emergency AC power source (s) in excess of the number i

]

required to meet the minimum redundancy requirements

{

i (i.e. single failure) for safe shutdown is assumed to 1

l be available and may be designated as an Alternate AC f

r

{

Power Source (s) provided it meets the Alternate AC j

i t

l power criteria in Appendix B."

I i

l l

107 [ Q:

Under the definition of station blackout, can a j

V single failure or DBA be assumed to occur at the J

unaffected unit?

l l

t i

I 4

~ _. -

-, -.. -. ~. - _ _. -

A:

At a multi-unit site, station blackout affects only

~T' sg l

4 one unit..Thi 7.. th Aunaffected unit ir ' P e d Mt M 4 d*G4A bu M q

'ircrring _;;i;,

nf a single failurg'endjDBA b_r -_'

meet be considered.

t j

108.

Q:

Is maintenance factored into the single failure l

criterion?

l l

As Yes.

Maintenance and other down-time events are i

i factored in; the single failure critorion should not i

be applied to these events.

109pe Q:

Can AAC be used for peaking?

I 1

J At Yes.

l 5

)

s_

l 110.

Q:

If a plant had four diesels at one statioD lhat w j

i not mally connected and heeded two. could i

I credit be ta for' he other two as an AAC source?

t j

I

/

i l

l l

A:

Y s, if they can be shown to sa y the Alternat I

i AAC criteria in NUMARC 87-00, Appendix 4

l 111.

Q:

If a plant installs a dedicated diesel generator for l

l

{

RCP seal injection, will that diesel be available l

l f

J

during a station blackout even though it is assumed that all AC power is lost?

At The SB0 rule does not require that all AC power be losts the rule requires that off-site power and on-sito emergency AC power required for minimum redundancy be lost.

112.

Q:

In the definition for "station blackout" does "proferred" mean "offsite"?

At Yes, there should be a "normal preferred" and "alternate preferred" offsite power source.

113.

Q:

When an emergency diesel is lost, does tha failure b/

include the bus work and cables?

i A:

No, just the machine.

/:

Can credit be given for some portion of the 114.

Q switchyard being energized by an AAC source?

A:

No.

An AAC source must be independent of the onsite emergency system and the preferred power system, so it cannot pass through or be associated with the j

switchyards unless the AAC source can be isolated I

t

. t 4

from the switchyard with en independent, isolated line for SBO use.

APPENDIX Bt ALTERNATE AC POWER CRITERIA 115.

Qt Under criterion B.3, what types of wind velocities l

should the AAC structure be able to withstand?

At Thc structure must meet the Uniform Building Code for your area which factors in wind velocities, snow loadings, etc.

116.

Q:

Does criteria B.3, preclude the use of aerial lines?

d.M / Y h t I

2 A:

Aeriallinesmaybeacceptableiftheyguricr

'"e-likelf[eathereventsforthesitearea($M O C-f 3

1 punw c-n~ )

d:t:r i.: khat a likely vaather-related 117.

Q:

_ f: U:

event g w4 Ac[bba 1* A f i

A:

These are the weather events considered in a

i formulating the Uniform Building code for your area.

i Therefore, if you meet the building code you have designed for the likely weather-related events.

l a

118.

Q:

Are criteria B.4 and B.6 essentially the same?

I I

At Both address separation criteria.

0 4 N 8eo f

g % ~r-3.c ~ aac~) M 119.

Q:

If you have four identical diesel generators, how do i

i you address common mode failure concerns?

1 i

A Satisfying the criteria in B.8 adequately minimizes l

the potential for common mode failure.

i 1

i j

120.

In Appendix B, common cause failure criterion B.8.f

)

states that the AAC power system shall be capable of 1

j operating during and after a station blackout without any support systems powered from the preferred or i

blacked-out units' class 1E power sources.

What is 1

)

meant by "suppopt systems"?

i j

At Support systems would include cooling, lubrication, i

air supplies, exhaust and any other features required for the proper functioning of the AAc power source.

i l

Q sL.Adm 121.

Q:

Under B.9 does t' vet mean hot shutdown or cold shutdown?

I 1

At The definition of safe shutdown in Appendix A is hot

)

i j

shutdown or hot standby as appropriate for your plant l

l l

as defined in your technical specifications.

You j

r I

i

\\

\\

l

{

l

also have the option of cooling the plant down if your EOPs call for this.

122.

Q:

In criterion B.10, if you are using adjacent unit Class 1E EDGs as your Alternate AC power source, de l

you have to shutdown the adjacent unit in order to test the diesels?

A:

No.

It is not intended to take a plant off-line to test diesels.

The adjacent unit diesels are covered i

by your existing technical specifications.

Therefore, testing in accordance with your technical specifications satisfies B.10.

1 I

123.

Q:

Will there be technical specifications for allowed outage times for the AAC scurce?

A As stated in Reg. Guide 1.155, technical specifications may be required pending resolution of the Commissioners' interim policy statenent en technical specifications.

I 124.

Q:

If you are using a hydro unit as AAC and take it out of service for a three month outage, how do you meet the 95% availability requirement?

1

\\

At You would not meet the availability requirement.

An on-line AAC source must have an availability of

.95.

Care should be taken in selecting an AAC source to ensure this requirement is net.

125.

Q:

Under B.13, is this an historical reliability or one you must maintain?

At One you must maintain.

t 12,6.

Q:

Do you have to have the data available to prove this reliability?

A:

Yes.

127.

Q:

How do you handle the reliability issue if you have more than one AAC machine?

At You would treat the multiple AAC sources as a system and show a system reliability of.95.

For example, if you had eight IC tuzbines at a peaking station and only need one for an AAC source then you would meet the reliability requirements for AAC, as long as your aggregate reliability for the peaking station was

.95.

\\

. i i

t 128.

Q:

For a diesel in the non-blacked out unit to qualify as AAC, would it have to assume all the shutdown loads for both units for the determined coping duration period?

As Yes.

This dierel must be capable of supplying one train of shutdown loads for each unit.

APPENDIX Ct SAMPLE AAC CONFIGURATIONS 129.

Q:

Is the AAC source required to be tied directly into the emergency bus?

A No.

Q '&&k 130.

Q:

Is an AAC source connected to a non-safety bus required to be pensanently tied into the bus or does it just need to have the capabilityk % M #~#5 The AAC power e,urce is not required to be At r

permanently connected to the non-safety bus as long as it fulfills all of the Appendix B criteria which includes the capability to be ready to load within V

M O '

b

• Y kM+ j one hour.

pyl 4

W-u

/tw<

1

~pu.

131.

Q:

If a multi-unit site has a 2/3 diesel configuration

]

and it can be shown by analysis that one diesel has the capability to shut down both units and the proper

?

l cross-tie capability exists, is it possible to J

c consider one of the diesels as an AAC machine?

j A ya.Appendix B criteria excludes the use of an adjacent unit's Class 1E power source from being considered as l4 -y -t e

i an AAC power source for,k#A shared and 2/3 emergency i

/\\

\\

]

AC power configurations for multi-ianit sitos due to 4

the requirement of considering a single failure at i

1 the non-blacked out unit.

i c

i i

4]

132.

Q:

Are breakers that are necessary for the operation of l

AAC power required to be operated from a controller i

j or can they be operated manually?

j At Manualoperationofbreaker;isallowedaslongasit I

can be demonstrated that the necessary actions can be 1

t I

is

'dsLkN i

carried out such that the

.'.A 5 &r sourcb.T ^"/0 N*

l ff Ls%

'* h

~ d0 M I

mR.4 MJavailable within one hour. % M(r. < lypy ( _ ypso $4g l

f l

I SA l'l.

V j /u q.v.s t I

j 133 In the case, f AAC configuration 2B,'i4-diesel,s l

l

~~'h batteries the cross-ti eakers and we i

5

/

I TC assume tha G s fat d then be necess to provide operator actions to supply p i

l

I i

$2 -

~

to the blacked out unit.

Dous thin mean that the AAC source would not be able to be considered as a 10-minute AC sour.,o?

A In order for an AAC source to meet the 10-minuto criteria circuit breakers necessary to bring power to safe shutdown buses must be capable of being actuated in the control room in that period.

134.

Q:

on AAC configur3 tion 2B, are cross-ties required for both trains?

Ytc.

SN At 4tE7 A single cross-tie would satisfy the g

requirementsA d u % E8'W A#S 24 ["

su m (fta 4 -~

~ffe s Qi 135.

Qt In # case where the reliability of a diesel is less than.95, would a utility assume that diosol to be the one that failed?

.4rM hM *,/d*(

• "f>

%, %, 9 J4 14 A A.,

am%,

[orstationblackouttheminimumreliabilitythatcan A

be committed to is.95.

Should the reliability of a particular diesel fall below that figure, actions to be identified under resolutisn of Generic Issue B-56 should be taken to increase the reliability in order to meet the target.

i f,

i C-c 136.

Q: -QReg the AAC power source loose *no feed only one bus?

a 1

]

As Yes.

Since a single failure need not be assumed at I

the plant concurrent with the station blackout, all l

loads that are nonnally available to the bus are MW dll /4 available.

f 137.

Q:

Can the transmission lines from the AA ources in s

l onfigurations 3A and 3B be sepa a e transmission line r do they have to be e lir.es normally run from the ource?

i

)

A6 The transmi on lines an be separate from the l

3 normal ' stribu, tion system it is protected from j

sev te vaather events in the vi ity of the site and 1

i t meets the criteria of Appendix B NUMARC 87-00.

e j

13 Q:

AAC configuration 2B displays two breaker tween IE

' ar sources to both p.tante.

breaker back-up efiel ewer f

j 1rousse req ' red with c s 1E power sources?

j At No.

al breaker opera '

is acceptable.

4 i

139 Q:

Are there any criteria for the distance between

\\

transformers for A,'.c cources? 9

• Mr, h;. a :: N

- 54 O

protected -the canc as the inuv4aing cransTristion

-HTreT7' y,, (k m, & W & /A~ S SA

% b Equipmnnt nn-c4*e tranc f err.cre) are cenridered-A:

Ms-).peiuir suusvesCly & M )

(2.0.,

-__'"CC,,;L vQ-h extremel" k ' likelihd.

and hav 1~

&_,~,$ b. *uvv.Y Y

& re-W&

W A

6 ea gy tornauves.

conse g o,ui wue

-n3 m

h[m Da i

~

/. "an<o w m'.~,s.

,, --c-mm ouyo s o w wu uewween u

W.W >L N,Q /&wl

.k mb

/

--com P a " % u v Ancoming transwo;icr ' _e_

140.

Should a peaking unit that is being used as an AAC source be looked at from an availability or reliability view point?

A:

Since a peaking unit is not usually on-line, reliability would be the appropriate parameter.

APPENDIX F ASSESSMENTS OF EQUIPMENT OPERABILITY IN DOMINANT AREAS UNDER STATION BLACKOUT CONDITIONS 141.

Q:

Must all equipment used for station blackout response have a demonstration of reasonable assurance of operability?

A:

No.

Only station blackout response equipment which is located in dominant areas of concern noods to be evaluated for reasonable assurance of operability in

accordance with NUMARC 87-00, Section 7.2.4 and g

I k' 1' I A

Appendix F.

W/

k puQ% :

ul#~Ck. *( ^ ~ W.

Y. w RULE Reft?O_EfB FgANgD LAC EDULEA s< -< st~ %.

142.

During the period required to perform modifications to install AAC, will the NRC require plants to demonstrate the ability to cope for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> and write corresponding procedures?

A:

No.

No interim coping capability is necessary to cope while modifications are being made.

Licensees must 7 _y-show that after the proposed modifications Are made, they will be able to cope for the applicable duration.

If you will be using AAC, you do not need to write procedures for AC independent coping pending the AAC installation.

&q ff 143.

Q:

When do T modifications mentioned in the last paragraph of the generic response need to be completed?

A:

The required modifications and a proposed schedule for completion must be identified in the 270 day However, the modificatidns. M M M W e' c.

't be response.

started until the Staff sends you an SER, becaura y^ t

don't knca whethrr *hav vill =aree with y:2r p

' c ~The proposed schedule should therefore give the number of years or refueling cutages followina the receipt of the SER required to complete the modifications.

Licensees have 30 days following the SER in which to confirm or modify their proposed schedule.

144.

Q:

The response format calls for the submittal of a one-line diagram of the AAC power source.

How detailed should the AAC one-line diagram be?

A:

The NRC has indiceted that a one-line diagram commensurate with that found in an FSAR or in NUMARC l

87-00, Section C would be sufficient.

l I

', n c. C.s'cy Q l

September 21, 1988 NUMARC 87-00 Errata Sheet for Industry 1.

P.

2 Section 2.5.1, should read:

"Sources of expected PWR and BWR reactor coolant inventory loss include (1) normal system leakage, (2) losses from

~

letdown, (3) losses due tc reactor coolant pump seal leakage and (4) BWR inventory loss due to SRV cycling and ADS actuation.

Expected rates of reactor coolant inventory loss under station blackout conditions are not expected to result in core uncovering for a PWR or more than a momentary core uncovering for a BWR in the four-hour time period.

l Therefore, makeup 9ystems in addition to those currently available unde. blackout conditions are not expected to be required.

As a result, it is expected chat sufficient head exists to maintain core cooling under natural circulation (including reflux boiling).

2.

P.

2 Section 2.7.2(3) - insert the following sentence before the last sentence:

"Additionally, it is expected that operators act within the first hour to establish a stable independent decay heat removal mode which is a significant factor in the plant's ability to cope with a station blackout."

NUMARC 87-00 Errate Shast for Industry Pegs 2 3.

P. 2 Section 2.11.2 - add to the end of the last sentence of the paragraph that begins "With EDG testing.

"following reactor shutdown."

4.

P.

3 Table 3-Sa - matrix location (SW2, ESW2) should read "P1".

5.

P.

3 Table 3-5b - matrix location (SW2, ESW2) should read "P1"; matrix location (SW2, ESW3) should read "P2*".

6.

P.

3 Table 3-6b inatrix location (SW3, ESW3) should read "P3*".

7.

P.

3 Part 2.B.A.

insert:

between "supplies" and "necessary" the following:

"on a per unit basis" l

l delete:

"during a station blackout on a per unit l

T basis."

i insert:

"following a loss of offsite power."

F 8.

P.

3 Part 2.B.B.

delete:

"during a station blackout for all units at the site."

insert:

"following a loss of offsite power."

1 l

r l

l i

r

[^

,,, - i

s NUMARC 87-00 Erratc Shsct for Industry Paga 3 9.

P. 3 Table 3 add an asterisk after the heading 1

"Supplies Available".

10.

P.

3 Table 3 Note beginning with "Shared" -

delete:

"concurrently".

11.

P.

3 Section 3.2.3 - clarify item (1) :

"(1) CALCULATE THE MOST RECENT EDG RELIABILITY FOR EACH EDG BASED ON THE LAST 20, 50, AND 100 DEMANDS (USING DEFINITIONS AND METHODOLOGY CONTAINED IN SECTION 2 OF NSAC-108 OR EQUIVALENT). "

12.

P.

3 Table 3 The "Required Coping Duration Category" on the la,st line should be "S".

13.

P.

4 Section 4. 2.1(10) (d) - delete ", as required."

14.

P. 4 Section 4.3.1 - strike the -last' sentence of item (13).

15.

P.

4 Section 4.3.3, item (1):

[

In the fourth sentence, delete "sufficiently" after "load-tested."

i i

Strike the last sentence.

l I

NUMARC 87-00 Errata Shsst for Industry Page 4 16.

P.

4 Section 4.3.3 - in item (4), delete "significantly" in the second sentence of the paragraph beginning "Section 7 of these guidelines.

J 17.

P.

7 Section 7.2.1 - first paragraph -

delete:

"required duration" insert:

"coping duration required in Section 3.2.5."

18.

P.

7 Section 7.2.1, Step 2 - after "removal" in the first sentence -

insert:

"for the coping duration required in Section 3.2.5".

19.

P. 7 Section 7.,2.1, Step 2 -

delete:

"B = A* (22.12 GAL /MWt) + C" insert:

"B = A* (X GAL /MWt)

+C Where X = 13.14 for 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> 22.12 for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> 35.55 for 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> 62.9 for 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> For plants using the one-hour AAC approach, the amount of water that needs to be provided independent of AC power in the first hour of their total

NUMARC 87-00 Errets Sho?t for Inductry Ptga 5 required coping duration is determined by the following formula:

B = A* (7.77 GAL /MWt) + C."

20.

P. 7 Section 7.2.1 - insert "heat" in the last sentence before the "Results" heading between "decay" and "for."

21.

P. 7 Section 7.2.1 - add an additional bullet:

"o The Step 2 formula was developed using 3000 MWt and a 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> duration, with sensitivity analyses being performed for a range of 2000 to 4000 MWt."

22.

P.

7 Section 7.2.2, Step 1(b) under heading "Battery capacity Calculatiqn --- No Load Stripping" - after "one hour" insert:

"(assumes battery charger is powered from AAC source)."

23.

P.

7 Section 7.2.2 - under heading "Battery Capacity Calculation --- No Load Stripping" - revise the "Note" in "Step 1":

"If an existing battery capacity exceeds the above capacity the rated battery capacity should not be reduced solely on the basis of the above station blackout criteria."

- i NUMARC 87-00 Errcta Shast for Industry Page 6 24.

P.

7 Section 7.2.3, Step 2 - first sentence - after "sources" - the remainder of the sentence should read:

"for the coping duration required in Section 3.2.5 (one hour for AAC plants if the compressor is on the AAC supply)."

25.

P.

7 Section 7.2.4 - second paragraph - after "systems" -

insert:

"in all dominant areas of concern"

26. PP. 7-13, 7-14, 7-15, 7 Section 7.2.4, Steps 1(1),

2 (1), 3 (1), 4 (1), 5.1(1), 5.2(1), 5.3(1) and 5.4(1) should read:

"Steam Driven AFW Pumo Room (PWRs only)"

27.

P.

7 Section 7.2.4, Step 2 - NOTE, delete the word "information", between the words "used" and "to" and add "

(Q) " between "rates" and "for."

28.

P.

7 Section 7.2.4, Step 3 - insert "A different temperature may be used if it can be justified based on actual measurement." as an added second paragraph.

29.

P.

7 Section 7.2.4, Step 3 - the second paragraph should read:

"It is assumed that the wall temperature does not change appreciably throughout the transient as shown in Appendix E

is s

NUMARC 87-00 Errate Shsst for Industry Page 7 (i.e., an increase of 2.5 C or 4.5 F during a 4-hour period)."

30.

P.

7 Section 7.2.4 - insert " (Q) " at end of caption "Methodoloav for Determinina Heat Generation Rates."

31.

P.

7 Section 7.2.5 - second paragraph - third line -

delete:

"identified in technical specifications" 32.

P.

7 Section 7.2.5, Step 1 - first line -

delete:

"identified in technical specifications" 33.

P. A Appendix A - include a definition for Hurricane Induced LOOP after the definition of "Alternate AC Power Source":

"Hurricane Induced LOOP - for the purpose of this document, is considered to coincide with anticipated hurricane arrival at the site; and the appropriate indicator is sustained wind speeds at the site in excess of 73 mph."

34.

P. C The "A" buses should be connected to each other and the "B" buses should also be connected to each other.

Fo" Unit 2 change the "A"

to "B" and the "B"

to "A".

r 1

.. s a

NUMARC 87-00 Errata Shast for Industry Pzg3 8 35.

P.

E Appendix E, Section E.3.2 in second to last sentence change "72 F" to "68 F" and in last sentence insert U

"(79 F) " af ter "44 C. "

36. PP. F-1 through F-4 delete in entirety and replace with Appendix F, Revision 1 dated September 17, 1988 and the Topical Report dated September 17, 1988.

s l

l l

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1 1

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l 1

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