ML20059B738

Summary of 900425 CRGR Meeting 185.Response to Minutes Deferred Until CRGR Review Completed.List of Attendees Encl

ML20059B738
Person / Time
Issue date:	07/17/1990
From:	Jordan E Committee To Review Generic Requirements
To:	Taylor J NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO)
References
REF-GTECI-057, REF-GTECI-131, REF-GTECI-A-17, REF-GTECI-A-40, REF-GTECI-A-45, REF-GTECI-A-46, REF-GTECI-DC, REF-GTECI-NI, REF-GTECI-SC, REF-GTECI-SY, TASK-057, TASK-131, TASK-57, TASK-A-17, TASK-A-40, TASK-A-45, TASK-A-46, TASK-OR GL-88-20, NUDOCS 9008300042
Download: ML20059B738 (18)

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.i MEMORANDUM FOR:

- James M. Taylor-Executive Director-for Operations FROM:

Edward L. Jordan, Chairman l

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Committee to Review Generic Requirements-

SUBJECT:

. MINUTES OF CRGR MEETING NUMBER.185 m

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The Committee to Review Generic Requirements (CRGR) met on Wednesday, April 25, J.

1990 from 1:00-5:30 p.m.

A list of attendees at the meeting is attached L

-(Enclosure 1). The following item was addressed at the meeting:

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1.

The CRGR completed their review, begun at Meeting No. 183, of the proposed Generic. Letter.on Individual Plant Examination for Severe Accident Vulnerabilities Due to External Events (IPEEE).

The Committee l

recommended approval of the Generic Letter, subject to a number of revisions discussed with the staff at Meetings Nos.-183 and 185.which' l

will be coordinated with the CRGR staff.

The Committee also asked to see L

again (on a negative consent basis,.before final issuance of the IPEEE l

Generic Letter) a revised 50.54(f);ahalysis for the IPEEE proposal.

This i

. matter is discussed in Enclossare12".

0 L

.In accordance with'the E00's July,.18, 1983 directive concerning " Feedback and l

Closure of CRGR Reviews," a wr,if. ten response is. required from the cognizant L

office to report agreement or;; disagreement with the CRGR recommendations in L

these minutes.

The'0ffice/ response to these minutes is deferred until CRGR Th 6

' review is completed.

.f,e6 fore,noRESresponsetothismemoisrequiredat-this time.

/

s Questions concernifig these meeting minutes should be referred to James H.

I Conran (492-9855).

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Denwood F. Ross n

[ Committee to Review Generic Edward L. Jordan, Chairman Requirements 4

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Enclosures:

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.SECY PDR(NRC/CRGR)'(w/o encl.)

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CRGR Members D. Ross D. Allison T. King

. Regional Administrators J. Conran P. Kadambi J. Sniezek

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'J..Lieberman S. Treby M. Taylor i

P. Norry M. Lesar C. McCracken

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.'y ENCLOSURE 1 d'0 ATTENDANCE LIST.

FOR CRGR MEETING NO.c185-Apiil 25,1990 i

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CRGR MEMBERS E. Jordan L..Reyes i

.G.; Arlotto-B.- Sheron F. Miraglia S. Lewis'(for.J. Moore) 11.

1 NRC STAFF D. Ross J.-Conran D.:Allison J. - Richardson '

R.-Kenneally

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.A. Murphy T. King i

W. Beckner L. Shao J.'Chen -

C. McCracken i

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l to the Minutes of CRGR Meetino No. 185 Proposed Generic Letter on Individual Plant Examinations for Severe Accident Vulnerabilities Due to External Events (IPEEE)

April 25, 1990 TOPIC The Committee completed their review (beg at Meeting No. 183) of the subject IPEEE proposal.

The staff addressed comuments and recommendations made by CRGR in the earlier meeting on the IPEEE proposal, and also provided a briefing on:

the relationship between proposed seismic vulnerability assessment activities specified in the IPEEE proposal for all operating plants, and the seismic ade-quacy assessment activiies-that will be required to implement-the resolution of USI A-46 in some of the older operating plants.

No briefing slides were' used by-the staff in their presentations _or discussions with the Committee at this meeting.

BACKGROUND 1.

The documents submitted initially to CRGR for review in this matter are listed in the Minutes for Meeting No. 183.

2.

In addition.to the documents in 1. above, the Committee considered coar -

ments on the IPEEE proposal (received subsequent to Meeting No. 183) that were submitted by the Nuclear Util' (NUBARG); see Attachment 2 to this inclosure.Backfitting and Reform Group CONCLUSICNS/RECOMEN0ATIONS As a result of their review of this matter, including tra discussions with the staf f at Meetings Nos.183 and 185,. the Committee recommended in favor of issuing the proposed IPEEE information request, subject to a nunner of modifications, to be closely coordinated'with the CRGR staff.

(The recommend-ations below that were made by the Committee at this meeting reinforce and, sucolement the CRGR comments and preliminary recommendations mace at Meeting No.183; see Attachment 1 to this Enclosure.)

1.

The Committee continued to question the staff's cost per plant estimate-(5400,-) for licensee performance of the IPEEE, reflected in the 50.54(f) analysts accomoanying the review pa.:kage.

The Committee felt that the estimate may be low; and it was noted that that estimate had also been

uestione6 by the ACRS.in their review cf this package, ano in the comments sut,mitted by NUBARG.

CRGR reiterated their earlier recommend-ation that the staff review carefully, and revise as appropriate, the cost' estimate for this proposed information request, based on the most recent experience with comprehensive external events analyses cerformed

ste (by either the licensees or tne NRC staff).

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2.

The Committee recommended that the 50.54(f) analysis for the IPEEE cacxage be revised to include actual examples of types of severe accident

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-vulnerabilitiesfdiscovered by external events analysos alresdy donc, where substantial safety improvements could be achieved in a cost effect---

ive manner, to better reflect the staff's view'(express 0d in the discus "

sions of this' item with CRGR) that there is a hiCh likelthood-that further such cost-effective improvements can be identified by conduct-of external event fm ad studies at all of the operating plants'.

- 3.

The Constittee recommen d that the staff provide in draft WREG-XXX (to; be issued for commer.t with the proposed !PEEE letter) a detailed discus-sion of: (a) the rationale for their-choice of RLE values specified in Tables 3.1 and 2.2'in Appendix 3 to the proposed IPEEE letter, and (b) the "binning" procedure employed by the staff.in categorizing the operating plants as shown in those Tables.

4 The Committee reiterated their earlier recommendation regarding coordin-ation of-seismic valkdowns specified separately in the approved USI A-46 resolution and in the proposed IPEEE guidance.

Although the staff-strongly prefers that the-licensees

• implementation-of USI A-46 not be delayed by the requested IPEEE effort, it should be made' cleat that at-the licensees $ ootion the two walkdowns may be scheduled by a licenses for performance at the same time to avoid unnecessary duplication of effort and. waste of rasources; 5.

Consistent with the approach taken in the IPE letter review,. the Commit-tee recommended that if any additional IPEEE implementation guidance ist i

found necessary..either for licensees or for staff reviewers of IPEEE submittals, it should be submitted for CRGR review.

Further, during the course of the first few IPEEE submittal. reviews, before ~any evaluations-of IPEEE submittal adequacy are issued to individual licensees-(particu-larly any requiring additional analyses or. involving staff proposed plant

'mofifications), the staff should meet-with CRGR to brief them..on progress of the review effort and discuss the adequacy of staff guidance / criteria useo in: the conduct of^ staff reviews of :IPEEE submittals.

These are particularly imoortant considerations fin-the IPEEE context because of the generally greater oegree of uncertainty associated with IPEEE analysts:

.(in comparison-to IPE analyses); for this reason also, the staff thould maxe provision explicitly in the IPEEE package for the possibility of issuing a s yplement to the proposed IPEEE letter, if necessary, to take into account comments'or cuestions raised by licensees or other members of e puolic in the planned IPEEE workshop.

6.

The Committee recommended that, during their review of IPEEE submittals,

.t the staff should serve as a clearing house to ensure that important IPEEE finoings by individual licensees are timely disseminated to all licensees.

The hmmittee recommenced that the staf f reexamine the projecteo schedule for use of IPEEE information set forth in the 50.54(f) analysis vis-a vis the Commission's five-year plan, to ensure that the 3-4 staff years allo-catea for NRC review of expected IPEEE submittals and followuo is con-sistent with the strategic planning'assumotions that have been acoroved

y =e Commission.

8.

The Committee recommended at this meeting a number of specific wcrding enanges to the proposed IPEEE letter / package that supplement those made

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earlier at Meeting No. 183 (see Attachment 1); principal among these were the following:

Prc:esed IPEEE Letter General comment - The staff should review again the proposed IPEEE a.

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letter in comparison to the IPE letter (GL ca-20), and conform the; two letters as closely as possible with regard to format and specific wording where possible (e.g., in the Summary, Examination Process, Ust, of IPEEE Results,.aod Accident Manaaement sections of i

the proposed letter).

Major deviations from previously approved wording in GL 88-20 in those sections should be justified by the i

staff.

b.

Page 2 - Provide a basic definition of external events at the begin-L ning of the section on " Identification of External Hazards".

L Page 3 - At the top of the page clarify the basis for the staff

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c.

L choice of the five external even,ts to be included in the IPEEE.

Also, clarify that all licensees are requested to address the (minimum) five external hazards; but some licensees with well.

known plant unique hazards (e.g,, prrximity to a volcano, light-i i

ning strikes affecting more than just loss-of-offsite power history, etc.) should plan to assess those hazards as well in their IPEEEs.

d.

Page 3 - Delete the narrative deceription of, and simply list, the five external events intended to be addressed by P.11 licensees in-l the~IPEEE.

Page 4 - Indicate that, for a seismic PRA, the hazard curves e.

developed by LLNL and EPRI, if available, should both be used by licensou f.

Page 4 -

the dist.ussion of seismic margins methods (SMs):

s (i) delets.eferences to specific plants, and simply inoicate that SMMs are not suitable for plants located in high seismic areas; and (ii) note specificall / that_the review level earthquake (RLE) j l

values, established by the staff and given in Appendix 3, Table 3.1 b

for use in the seismic portion of the IPEEE (if the SMM option.is

nosen), co not constitute safety acequacy criteria or vulnerability

" thresholds" for the plants indicated.

(See item J. below for l.~

further discussion of the intended use of RLEs in determining the reporting of IPEEE.esults by licenseesi Page 5 - In the section on " Internal Fires", restructure and clarify g.

the intent of the sentence referring to Fire Risk Scoping Study issues that are to be addressed in the IPEEE.

Pages 5 ano 14 - In the section on n.

"High Winds,...", clarify that in Step 3 of the process shown in Figure 1 the licensee should first cetermine if the 1975 SRP criteria (not " current" criteria) are met

'n his plant; if not, tne licensee shoulo continue the assassment sing the recommenced optional steps (i.e., 4, 5, and/or 6).

[See also items ao, and aq. below.J.

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Pages 5, 6,- and 7 - Rewrite completely the section entitled "Coord-ination with other External Events Programs" to make clearer the

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current status of the USIs and GSIs referred to there and their i

relationship to the IPEEE.

For example, (i) state clearly that USI A-45, GI-131, and the Charlestown Earthquake Issue are subsumed into the IPEEE and successful completion of the IPEEE will constitute full resolution of those issuasi-(tt) note that provisions have been

)

made for licensees to address i planned USI A-46 walkdowns, the seismic systems interactions portion of USI A-17 and the seismic i

capability of safety tanks question of USI A-40 as well; also clarify the relationship between the combined USI A-46/17/40 l

walkdowns and the seismic IPEEE, emphasizing the need for close coordination in these areas to avoid unnecessary duplication of effort by affected licensees; and (iii) make clearer that the licensees' IPEEE analyses of issues identified in the fire Risk Scoping Study will contribute i

to resolution of GI-57; but the IPEEE fire analyses plant modifications proposed by licensees) may or may(and resulting not constitute complete resolution of GI-57, depending upon the outcome of separate research studies now being conducted under the GI-57 action plan.

j.

Page 7 - Modify the second paragraph under " Severe Accident Sequence Selection" to clarify that a HCLPF value lower than the ALE specif-ied for a given plant does not necessarily represant a plant vulner-ability, but.rather defines a " reporting" level (i.e., a threshele y

criterien fo* further evaluation and inclusion in the report of IPEEE results).

The licensee should assess the significance value lower 1than the specified RLE, take any necessary of a HCLPF actions indi-cated, and make other plant modifications that he deems appropriate' to improve identified vulnerabilities.

o k.

Page 8 - Delete the first paragraph under "Use of IPEEE Results; Licensee".

1.

Page 9 - Delete the first paragraph under " Accident Management"; and i

revise the first sentence of the second paragraph to say simply that licensees need not develop an accident management plan as part of their IPEEE effort.

Page 9 - Change the next-to-last sentence under " Documentation of m.

Examination Results" to indicate that NUREG-XXX specifies-the minimum information to be documented / submitted in connection with licensee's IPEEE.

Page 10 - Change the first sentence under "Licensec Resrans7'- to n.

indicate that NUREG-XXX provides guidance for the submittal (not reporting) of IPEEE results.

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Page 10 - In the fourth paragraph, add a provision to consider o.

requests for extension of the time period to submit the IPEEE report, where licensees choose to perform the IPE and the IPEEE in l

series.

Page 15 - Change the title of Appendix 1 to "3ummary of Seismic p.

IPEEE Methodology Ehancements".

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Page 16 - Change the first sentence of.the second paragraph of 4

Appendix 2 to reflect that the IPEEE containment performance evaluation is intanced examine systematically whether there are sequences that involvc failure modes distinctly cifferent than those found in the IPE that contribute'significantly to containment functional failure, Page 17 - See item j. above, and make conforming c.ianges to the last r.

sentence in Appendix 3.

Page 18 - Add a footnote to Tabls 3.1 explaining the origin of and.

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rationale for the 0.Sg RLE " bin".

Page 19 - In Table 3.2, instead of specifying that a seismic PRA is t.

" required" for.Diablo Canyon and San Onofre, simply indicate that seismic margins methods in their current form are not applicable to those sites.

i Page 20 - In the second paragraph of Appendix 4, add the provision-u.

that a11 im>ortant assumptions should be included in the licensee's 3

report of I'EEE results.

Page 21 - Change the title of section 4.114 to " Submittal of i

v.

Vulnerability Definition and Potential Plant Improvements".

Also.

Mhte the second sentence of that section, snd revise the first

'3 sentence i.c specify simply that licensees provide a disctission of how "vulnerab?lity" is defined for their plant for each 1.tternal evt" avaluatec.

l Page 2 - See item u. above, and make a conforming change in item 1.

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of section 4.2.1.

Page 23 -.Delets items 9, 10, and 12 in section 4.2.1; these x.

L documentation items are already specified explicitly in sections

'4.1.4 and 4.1.5.

(For similar reasons, make conforming deletions l

also in section 4.2.2 (for both-full-scope and reducec-scope SM reviews), and in sections 4.3 and 4.4.)

y.

Page 23 Clarify the intent nf item 13 is section 4.'2.1 by l

eferring to the applicaole specific guidance in craft NUREG-XXX for L

more detailed ciscussion.

(Make a similar clarifying change to item 3 of section 4.4.]

Dage 27 - In item 4. of section 4.4, clarify that licensees are to i

l evaluate the results of their plant / facility review to determine geir robustness in relation to (instead of "conformance with")

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NRC's current criteria.

Dage 28 - Revise the wording of item 12 in section 4.4 to indicate sa.

more clearly that, in connection with the licensee's report of IPEEE esults, the staff requests certification that no other clant-unicue 9azard known to the licensee at the time of performance of the IPEEE

oses any significan', threat to the plant (in the context of the screening approach for "High Winds, Floods, and Others").

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Draf t Commission Paper on IPEEE e

Pages 3 and 4 - Revise the sentence that begins at the bottom of ab.

page 3 to indicate more clearly that, if the staff disgrees with a licensee's IPEEE determinations, and concludes that certain actions are necessary (i.e., required for adequate safety or compliance) or are otherwise justified (e.g., cost-justified substantial safety enhancement), the Commission's backfit rule (not " policy") will be applied in deciding further NRC actions.

Draft NUREG-XXX Page vii - Change the title of Ar ac.

ation and Reporting Guidelines". pendix C to " Detailed Document-Page xii - Jn the second paragraph under " Seismic E ants", delete ad.

the names of specific plants and refer instead to " California coastal sites".

(See also item f. above.)

p ae.

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• Delete the first sentence in item 3. under section 2.1, and combine the substance of the second sentence with item 2.

af.

Page 4 - Delete the words "Recent seismic" in item'7. under :,ection 2.1.

Page 5 - Revise the next-to-last sentence in section 2.4 to make it ag.

cere clearly consistent with the intended screening and assessment process specified in Fig. 5.1 with regard to application of current L

NRC (PMP) criteria, and indicate that the specific concerns to be addressed are onsite flooding effects and roof ponding.

Page 6 -- Add further discussion to section P 6 to indicate that thGt ah.

this section really only applies to sites where it is known that lightnir.g strikes are likely to cause more than just loss of offsite power.

ai.

Page 7 - Delete the second sentence under section 2.8, and note that loss-of-of fsite power and station blackout are addressed in the IPE.

aj.

Page 8 - Revise the discussion under section 2.11 to eliminate reference to specific plants (e.g., "..only a few sites located near active volcanoes need to consider volcanic activity.

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Dage 8 - Revise the last sentence under " Summary"to clarify that the ertification reouested by NRC regarding plant-unioue external events t

0ther than the five addressed explicitly in the IPEEE letter) relates to plant-specific hazards known to the licensee today.

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Dage 13 - In section 3.1.2.4. clarify intent by citing specific examoles of "nor. ismic failures" ind "'uman actions"

age 14 - Change the title of section 3.2.2 to " Review t.evel Earth-am.

Ouake and Associated Soectral Shapes; and begin the second sentence

7 of the introductory paragraph with the words "The seismic margins method..."

l Page 15 - Expand the second full sentence on the page (referring to an.

two eastern sites where a 0.5g RLE should be used) to better explain the basis or rationale for that RLE value.

Also, revise ~the next sentence to eliminate reference to specific facilities.

Pages 20 and 21 - See items s. and t. above, and make conforming ao.

changes to Tables 3.1 and 3.2 of-the NUREG.

i Page 24 - Revise / simplify the first paragraph under section 5.2 to ap.

. indicate that a licensee may choose to bypass one ca more of the optional steps shown in Figure 5.1, if the 1975 SRP (not current licensing) criteria are met, or.potentiel vulnerabilities are identified or demonstrated to be insignificant.

i Page 26 - In steo (3) of Figure 5.1, change " current licensing aq.

criteria" to "1975 SRP criteria".

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Pages 27 through 33 - Note item 1. above, and ensure that conformi a r.

changes are made throughout section 6. of the NUREG to be complet consistent with the summary discussion in section 5. (" Coordination")

of the proposed IPEEE letter.

Page 28 - In item 4. under section 6.2.2.1, change " current SSE" to as.

"existino SSE".

a t.

Pages 38 and 39 - Expand Appendix A of the NUREG in accordance with

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recommendation 3. above.

Page 43 - See item ac, above, and make conforming change here.

au.

Page 50 - See iten z. above, and make conforming changes in item 4.

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under section C.4.

i The sponsoring staff should coordinate closely with the CRGR staff all chan e

made to the IPEEE in resoonse to these recommendations.

On that basis, no turther review of the revisea package is necessary, except the Committee requestea to see again, on a negative consent basis, the revised 50.54(f) analysis for the IPEEE proposal before the revited package is forwarded to the E00 ana Commission for final consideration, i.

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M ENTS/ PRELIMINARY REcomENDATIONS 5

The Committee did not complete their review of the IPEEE package weting; April 25 was tentatively scheduled as the date-for. the completi the CRGR review of this ites.

The Committee offereo comments and preliminar r":oamendations in a number of areas discussed with the staff at th principal among these were the following:

1.

9 The staff.should give special ettention to the-schedule prescrfbed the A-45 and IPEEE walkdownst these related tasks should be coordinated, and enough flexibility alleved in scheduling by litens to avoid duplication of effort and unnecessary waste of resources e

2.

to better describe the staff's rationale.for the b d

Table 3.1 and 3.2 in the draft NUREG (e.g., 0.3g or 0.5g for the R Level Earthquake values for each plant).

The package should aise l

scheme that takes into account appropriately Hazards Curves.

3.

the 50.54(f) analysis included with the packag a

proposed generic letter should be er.panded, to better indicate the basis of the staff's estimate and the possible range of licensee costs that night be expected.

4 As currently written, the package is too easily read as imposino add tional requirements and adequate safety acceptance criteria that beyond the current licensing bases for existing plants, rather than reouestino a systematic search for severe accident vulnerabilities.

l -

package should be carefully reviewed for appropriate use of-such tones a The "teovired," "reguirement," "needed," " current criteria",'"RLE," etc the context of usage of those terms. -The package should be modified uously indicate (a) that the licensees are being re bases, for the purpose of identifying vulnerabilit l-beyond design basisn to :e comoared agair st are not being imposea by NRC (no i

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as acceptance criter'a to determine safety adecuacy of the operating

, at least) clants; and (c) if severe accident vulnernoilities are ioentified by the iicensees in the IPEEE process, they (i.e., the licensees) mine wnether/how it is appropriate to address them.

will deter-L To the extent possible, the staff should avoid discussion of specific facilitities in the generic IPEEE guidance; suca discussion can carry atn it unintenced negative connotation anc have the effect of focusing unwarranted Etention on an individual plant.

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'he stsff should clarify how/to wnat extent common mooe <aiiure oue to

stulated external events oeyono a plant's cesign basis must be treated in t e IPEEE (e.g., how many simultaneous failures across the entire AHached I

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3-i plant, due to a larger-than-design-basis earthquake, must be cons ririesse front centainment).in t',e 'searen for. vulnerabilities 7,

The staff should review any references in the proposed Generic specific contant of the draft NUREG, to try to avoid development of situation'where changes made to the draft NUREG (following the p I

workshop) also require changes to the Generic Letter.

8.

The treatment of accident management in the IPEEE context nee addressed further and clarified (e.g., at pp. 9 and 16 of the draft

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April 13,.'990 Mr. Edward L. Jordan Director, Office For Analysis and Evaluation of Operational Data United StateL Nuclear Regulatory Commission Washington, D.C.

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Subj:

Comments On Proposed Generic Letter Concerning Individual Plant Examination For External Events

Dear Mr. Jordan:

The Nuclear Utility Backfitting:and Reform Group (NUBARG)

't provides the following comments on the backfitting implications of the above-referenced proposed Generic Letter.

While we.

generally agree that developing plant-specific information on external events could be valuable in identifying the significance of risks' associated with such events, our members are concerned with the extensive scope of the proposed' Individual Plant Examination for External Events (IPTbt).

We first provide below some general comments on the Staff's' approach and then proceed to more detailed comments on particular aspects of the proposed-IPEEE program.

General Observations NUBARG believes that the proposed IPEEE program would benefit greatly from a systematic review of its licensing and backfitting implications.

Such a review could enable the NRC (1) to streamline the IPEEE by identifying areas.for which there is not an adequate basis to require additional examination, and.

(2) to integrate the IPEEE reviews with other.NRC programs in a more efficient manner.

This will allow for better utilization of limited licensee resources.

l In this regard, it is our understanding that the NRC.has not performed a regulatory analysis or cost analysis of the proposed IPEEE program.

NUBARG urges the NRC to develop a realistic estimate of the cost and burden of the IPEEE program before issuance of the Generic Letter.

In fact, during the joint M /e c ko~ e n l lo f~en c lo s u r e 2 i

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meeting on March 27, 1990 of the Advisory Committee on Reactor i

Safeguards (ACRS) Subcommittees on Extreme External Phenomena and Severe Accidents, similar concerns were raised regarding the Staff's rough estimate of costs for the IPEEE effort.

Specifically, the Staff indicated that the manpower effort was roughly estimated at three man-years with a cost of approximately J

$400,000.

ACRS members voiced considerable doubt concerning this estimate.

t To date, actual experience with implementing the Individual Plant Examination (IPE) effort indicates that the Staff's estimate may be significantly low.

As CRGR is aware, licensees expect to Fpend upwards of several million dollars on their IPE programs per. plant (compared with the $500,000 projected in the Staff's December.1, 1988 Evaluation for Generic Letter 88-20, which the Staff has agreed was not accurate).

The burden is especially great'for plants that did not have PRAs already-developed.

Because the Staff indicated during the ACRS meeting that they had used the same means of estimating manpower and costs for the IPEEE eff1rt as they had for IPE, we are concerned their estimates may again be significantly low.

CRGR should therefore ensure that a raalistic estimate of the resource and financial burden of the IP3EE effort is performed.

Part of the t

cost to be examined should include the NRC's own review of the.

IPEEE submittals, since lictnsees will likely be charged for the cost of NRC Staff review-(the cost for review of IPE submittals could be as high as $100,000 for some plants).

Principles of sound regulation, which are reflected in the NRC's backfitting 4

rule, 10 C.F.R. 5-50.109, dictate that the agency understand the L

resource burden of its programs before they are adopted.

This is particularly true hete since it is not clear how the l

IPEEE.results will be used.

For e,tample, the Staff's current L

thinking appears to be that the IPl: results, and presumably the L

IPEEE results as well, will not be used in assessing the acceptability of licensing actions.

In these circumstances, it is not clear why licensees are be3.ig asked to undertake a prog;'m of the magnitude of the IPEEE.

In addition, our review of the draft Generic Letter released in November 1989 as well as the NRC's External Events Steering Group report.(dated March, 1990 and which first became available on March 27, 1990) indicates that the IPEEE effort requires coordination with a number of NRC programs.

Although the Steering Group's report addresses _this issue, it appears that the NRC Staff intends to leave the specific details of this coordination process up to the individual risk analysts of each utility.

We are concerned that this approach could lead to duplicative effort on the part of licensees.

In addition, as discussed below, the schedule for the IPEEE should be better coordinated with the schedule for the IPE.

It is the responsibility of the agency, before adopting a new program, to

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h ensure that it is properly coordinated and prioritized with other I

ongoing work (see 10 C.F.R. 5 50.109 (c) (6)).

Soecific_Crmments 1.

Ipfy rnal Fires.

An example of potential duplication involves tna proposed evaluation of risks from fires.

Given the

+

extensive firo protection efforts already completed under 10 C.F.R. part 50, Appendix R.and related requirements,_there does not appear to be a strong. case for additional fire risk analysis.

The Steering Group's evaluation (at page 9)-reviewed the effect of Appendix R modifications at certain plants.

The evaluation indicates that the core damage frequency of the tuo plants for which meaningful data existed was reduced by a factor of ten and three respectively as a' result-of Appendix R modifications.

Other data appear inconclusive on the risk contribution from fires.

The fire PRAs performed to date indicate a very large range of uncertainty in *h. results.1 This is-due in large part to the absence of a csmplete real-world and experimental data base on several aspects relating to fire probabilistic analysis.

Moreover, it should be noted that the public risk'from internal fire scenarios has been shown to be negligible.

Containment performance as it applies to internal fires was examined in NUREG/CR-5042.

NUREG/CR-5042 found-that early containment failure and large-release scenarios were either

. absent or very minor contributors for the six reactors studied.

NUREG/CR-5042 at 3-5 to 3-6.

Thus, public risk from containment performance in fire scenarios should not ba a concern.

In any event, if.the internLi fire-portion of the IPEEE is retained, it is essential that the fire analysisLunder IPEEE not entail a re-review of issues already addressed under the uRC's fire protection requirements.

Such a re-examination would result in_a substantial expenditure of resour as-without any comparable benefit in safety.

It is 91so ess6atial that the 1PEEE analysis be based on= assumptions consistent with any Appendix R exemptions previously granted for the plant.

In granting exemptions, the NRC made findings that the plant configuration provided equivalent protection to that required by Appendix R.

CRGR should ensure that the IPEEE analysis will properly reflect the basis-for previous exemptions.

With respect to particular aspects of the program, there does not appear to be a sufficient basis to justify inclusion of

-seismically-induced fires as a potentially significant

,b'

-See NUREG/CR-5042, " Evaluation of External Hazards to Nuclear Power Plants in the United States," dated December 1987, at 3-6 to 3-9.

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t

-4 contributor to core damage.

Inclusion of seismically-induced fires appears to be based on the Sandia " Fire Risk Scoping Study," NUREG/CR-5088, dated January 1989.

In its discussion of this issue, however, the Sandia study reflected speculative assumptions without supporting data.

Egg NUREG/CR-5088 at 60-64.

In fact, the study (at page 61) noted that "there are no data on seismically induced fires in nuclear power plants, and hence there is ru) way to assess the seismically-induced fire initiating frequency."

Since seismically-induced fires have not been shown to be a concern in modern industrial facilities, their inclusion in the IPEEE should be questioned.

Seismically-induced fires.

often occur as a result of the rupture of cast iron natural gas pipelines.

Such cast iron piping is not found in modern industrial' facilities like nuclear power plants.

Studies of the damage following the earthquakes in Mexico City, Armenia and most recently in northern California did not reveal any evidence of fires in such industrial facilities.

other elements of the IPEEE that are derived from the Sandia

~

Fire Risk-Scoping Study --

e.g.,

effects of fire suppressants on safety equipment -- deserve careful consideration.

It is not clear from the draft Generic Letter or the External Events Steering Group report what the guidelines will be for reviewing these issues.

We also note that some of the Sandia conclusions in these areas have been based on overly cunservative assumptions.

With respect to.the effect of fire suppressants on safety equipment, a detailed industry evaluation of the events cited in draft NUREG/CR-5432, " Potential Impacts of Inadvertent Fire Suppression-System Activations in Commercial Nuclear Power Plants" (August 1989 draft), revealed that less than' twenty percent of the events involved damage to safety-related equipment and in no case was the redundaat piece of~ equipment disabled.

l In short, the issues raised in the Fire Risk Scoping Study simply reflect the fact that large uncertainties remain with the l-application cf PRA methodology to fire risk assessment.2 Given the uncertainties, licensees should not be asked to perform the' IPEEE for the purpose of advancing the state of the art in PRA research for fires, especially when there is not yet a suffielent basis for evaluating the accuracy or value of the results with a high degree of confidence.

2.

Seismic Events.

A substantial part of the proposed IPEEE effort relates to seismic issues.

As the Staff is wall l

L 2/

This does not imply, however, that the overall level of fire.

L protection provided by compliance with the NRC's detailed requirements in this area is somehow inadequate.

That is clearly not the case.

See comments of the Edison Electric Institute on the Sandia Fire Risk Scoping Study, NUREG/CR-5088, dated April 15, 1988.

l m.

4 5-l aware, it is essential that the IPEEE effort-be coordinated with the program under USI A-46 and related issues.

The walkdowns required for the IPEEE effort (i.e., either for a seismic PRA or margins analysis) are similar in nature to that requirt.d for resolution of USI-A-46 and may be combined with the USI A-46 walkdowns.

Based on current schedules, the walhuowns 'ar USI A-46 would be due before those required under,IPEEE.

Therefore, to ensure efficient utilization of licensee resources, we understand that the Staff will allow licensees to coordinate the 1

timing and other requirements of these efforts, and integrate them so_that only one walkdown is necessary.

We encourage this coordination of the two programs.

A potential area of concern involves the need for additional flexibility in the review required under IPEEE.

Specifically, licensees with facilities located east of the Rocky Mountains should be~given the option to choose which of the two existing seismic hazard estimates (l'.e., EPRI or LLNL) are best suited for their site for purposes of performing their seismic hazards-analysis.

Currently, the Staff would call for use of both the EPRI and LLNL studies (see Steering Group report at page 19).

Such an approach is very costly and does not appear to be justified in view of.the fact that the Staff has found both studies to be acceptable.

We are also concerned with potential duplication of effort for those plants for which reevaluations of the original seismic design have already been completed.

The proposed IPEEE would require plants to be evaluated against more stringent seismic requirements than applied during the original design.

Some plants have already conducted seismic design reviews against cr'teria more stringent than the original design basis.

The Staff should ensure that these facilities are not required to duolicate the previous effort.

In this regard, such facilitiec should be allowed to take credit for past seismic reviews, as appropriate, which meet or exceed the reviews contemplated under IPEEE.gnd refer to those reviews for purposes of satisfying the IPEEE l

3.

QthgI_ Events.

The Steering Group report, at page ll, states that licensees should assess the impact of the "new criteria" presented under the National Weather Service's latest I

probable maximum precipitation critoria.

Under Generic Letter 89-22, and revisions to the Standard Review Plan, these new I

criteria were only approved for application to :uturg plants.

1 2/

The same should be generally true for all plants that were included in the Systematic Evaluation Program ("SEP").

For any issues covered by the IPEEE which were previously addressed in the SEP reviews, the licensees should be allowed to refer to the previous reviews to satisfy the IPEEE.

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Y v

There is no explanation of why existing plants must now be reviewed'against the new criteria.

Again, better coordination of the NRC efforts is called for.

{

4.

Schednig.

The.IPEEE schedules should be coordinated vith the ongoing IPE effort.

The IPE submittals are due at the latest in the third quarter of 1992.

The IPEEE submittals are proposed to be due in November 1993.

This short interval between the two submittals may not be sufficient for licensees who will need to start their IPEEE in the middle of the IPE.

The IPE is a manpower intensive effort for licensees.

To-perform an adequate IPEEE and not fragment the IPE effort, a more realistic schedule is necessary.

We understand thht the NRC is considering establishing a schedule for the IPEEE that will run consecutively with that of the IPE.

We encourage such consecutive schedules in order to avoid overlap in the two programs. -As currently structured, the two programs overlap by two years.

A less burdensome-schodule, such as one calling for submittal of the IPEEE by September 1994, should be established..

5.

Reculatory Basis.

It is our understanding that the Staff has made no formal. regulatory analysis of the proposed IPEEE effort.-

This is apparently because the program is being treated not as a backfit under Section 50.109, but as an "information requeat" under 10 C.F.R. 5 50.54(f).

In either case, however, the proposed IPEEE program comes within the scope of the Commission's concern in adopting the 1985 backfitting rule and warrants careful analysis in a manner consistent with the Commission's backfitting policy.

The Commission has previously i

stated that:

The amendment of 5 50.54 (f) (adopted in the 1985 backfitting rule to require a justification for information requests] should be read as indicating a strong concern on the part of the Commission that extensive information requests be carefully scrutinized by staff management prior to initiating such requests.

The Commission recognizes that there may be instances where it is not clear whether a backfit will follow an information request.

Those cases should be resolved in favor of analysis.

L 50' Fed. Reg. 38097, 38102 (September 20, 1985).

l CRGR's observations in a similar case are equally applicable here.

Specifically, during its meeting on October 16, 1986, CRGR concluded that the Staf f's proposed use of a 5 50.54 (f) in'ormation request to resolve USI A-46 constituted a backfit.

In the minutes of that meeting, CRGR stated as follows:

The basis for this view was that under the proposed resolution the adequacy of the design of a licensee's

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I a'

facility would be judged against significant1y'uifferent criteria than were used by the staff in licensing the facility initially (i.e., the staff's position regarding what had to be done by the licensee to satisfy the requirements of the regulations had changed significantly and become more stringent).

These were clearly the type of circumstances contemplated by the commission in approving the backfit rule.

Secondly, the time and expense involved in developing:the seismic experience and seismic testing data bases, and the analyses involved in qualifying the equipment in the-l older plants by comparison with that data, is clearly greater than the "information request" contemplated'by the Commission in approving the section of 10=CFR 50.54 allowing such requests without resort to the complete working of the process called for in the backfit rule.

The Staff's current approach to the IPEEE program is not unlike that discussed by CRGR above.

Accordingly, a more' thorough review of the program's-scope and burden appears warranted.

Conclusion Ultimately, a hard look at the preoosed IPEEE will produce a better, more streamlined program that will utilize limited licensee _ resources more efficiently and avoid duplication of

. ef fort.. Even if no backfitting rule existed, we believe that prudent management of both NRC and licensee resources dictates that the Staff's proposal-be subjected to careful scrutiny to ensure that the program is adequately justified.

To further licensees' understanding of the Staff's efforts in this area, we also urge the NRC to make publicly available a revised draft of the proposed Generic Letter.

Should you have any questions regarding our comments, pl ase feel free to call.

Sinem&Iy g

]

bm Nichol s

S. kynolds Daniel I

S enger Perry 01 Ro ir son Counsel to Nuclear Utility Backfitting nd Reform Group cc:

James H.

Conran i

r 1

f