ML20237A061

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Forwards History of Facility Regulatory Performance, Including Tabulation of More Significant Milestones & Enforcement Actions.Remaining Items Will Be Provided within 1 Wk
ML20237A061
Person / Time
Site: Pilgrim
Issue date: 07/19/1986
From: Rehm T
NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO)
To: Delmedico J
NRC OFFICE OF CONGRESSIONAL AFFAIRS (OCA)
Shared Package
ML20237A042 List:
References
2.206, NUDOCS 8712140231
Download: ML20237A061 (10)
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Text

{{#Wiki_filter:- - - - .t Vnf - v-June 19,.1986 W, - $Q MEMCRANDUM FCR: Joe DelMedico, Congressional Affairs Officer Office of Congressional Affhirs. FROM: T. A. Rehm, Assistant for Operations Office of Executive Director for Operations

SUBJECT:

HISTORY OF REGULATORY PERFORMANCE AT PILGRIM POWER STATION in res;:ensa Oc Richard Ucell's recues: of June i,1926, this memertndum forwards a hist:ry of regulatery proolems reia:1ve to the Filgrim Nuclear Pcwer Statien. milestones and enforcement actiens, such as:This history includes a ti.b milestoner, civil penelties/ orders, significant mariagement meetings, sh enforcemesit conferences, and Innediate/ Confirmatory Action letters, I a:tc ackr.:.iedge his sa::lemer.tal recuest for five specific 1:grs; hcweve since 1: wi:' rectice mere time :: develep, we have decided r.c: tablatien and we will provide thc ether items in at: cut a week.

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i 1 i 4^*& ,.( ffL'! RIM STAT.t0N 04de No. 50-30c J r-l l EES't.ATORY p proypy(5 97gyngy \\ l A tabulation of sienin mj1es.cnes and enfor:n.een; at:f ens 'ct.- I \\ j. '4 j 9 4 g. I e I i i l 1 I I s )

j February 19EC A civil penal:y (!!,000) was assessac f:r shipping radioactive materials with externai radiation levels in excess of regula: cry l imi ts.- March 1981 (SALP) Management meeting to discuss the results of the SALP fer the perf od January 1,19E0 to Cecacer 31, 1980. April 1981 A civil ptnalty (513,000) was assessed for events su. rounding movement of irradiated fuel without secondary containment as identified in inspection report SC-2S3/80-09. July 1951 A manage:en meeting was heic in July 1951 :: ciscuss c:ncarns for TMI Acticn P?an Items J i involving post accident sampling pr:cedures and equipment and an Irrmediate Action Letter was inued regarding implementation of these ) 1 itemst Meetin rac%:icn prc:g was prompted by a' June 19El-cencn inspecticn i (EC-292/51-14) f enc the licensee failed t: c:r.f:rm with NRC criteria in c:nnecticn with 4 of the 5 NUREG-0578 Categcry A items inspected. June - September 1981 Inspections 50-293/81-18 and 81-22 identi fied ( six prM1 ems; inccerahlt combustible gas c:ntrel system; failure to perf:rm an adecuate 50.59 review; failure :s pr: vide a::M:riate pr:cedures and drawings; fa;iure { U m8 e a repor: recuirec by Tecnnicai \\ Specifica:icns; faiiure to provide accurate iMermation to NRC; 'and failure to satisfy \\ u Limiting Candition for Operz:icn (LCO) vegarding primary containment 4sciaticn \\ valves. These it,s;ections were subsequently the subject of enfor:ement acticns taken in s January 1982. Jii9 - August 1981 d A Per ermance Aporaisal In:pecticn (50-292/ 81-20) fcund 6 of 8 areas examined belew average. These were: c mmittee activities ; quality assurance audits; maintenance; c:r ective action systems; licensed and non-licensed : raining; and pr:curemen:. F an: eperations and design changes and mcdifica-tien: us ri: fcund te be average; hcwever, significant weaknesses t,ere identified in ( bcth areas. (

Cct::er 19E1 Enfer:cment conference to discuss management centrols of safety related activities in-ciuding the violations identified during inspections 50-2S3/81-18~and 81-22, the Performance Appraisal Inspection results, and an interim SALP review (pericd September 1, 1980 - August 31, 1981). January 1982 Civil penalty (5550,000) assessed for failure to comply with requirements of 10 CFR 50.44; submittal cnf false information to NRC and subsequent delay of notification to NRC of known inaccurate information; and failure to ecmply with LCO for RCIC c:ntainmen; isolation valves. (P1P) Order modifying license required licensee to submit a comprehensive plan of action that would yield an independent appraisal of.. sits and corporate management, ree:mmendatiens-ter improvements in management c:ntrolst ard oversight, and a re"iew cf previ:us ::m~ pliance with SRC requirements. Management meeting to discuss implementing requirements of tne NOV/preposed civil I. . penalty and order modifying license regarding the independent appraisal of Besten Edisen C mpany (5Eco) management prt:ti:es. January *?22 Ins:ecticn re:cr: 50-292/31'25 icentified a severity level III violation for transporta-tien of radioactive ma:erials with liquid in the containers. This violatien was based en an inspection in Aucust 1981 by the State of South Carolina which resulted in issuance of a civil penalty ($1,000). March 1982 Bost:n Edisen Company (SEco) submit ed the Per'ormance Improvement Pr: gram (PIP) required by the January 1922 Order. NRC Managemen; meetings t: review status of the Performance Improvement Pr: gram were held accrexdmately every six weeks until Septem:er 1964 4 _ _ _, _ _ _ _ - _ - - - - - - - " - - - - - ' ' ^ " - " - ' "

JuneLISEZ. A special inspection (50-293/82-20) c:nducted .of licensee actions after-radioactive spen: resin was found on roof to within the protected area.ps and pavement Nc. violations L identified. Confirmatory Action Letter issued concerning actions to be taken regarding the spent resin. July 1982 Enforcement Conference to discuss exceadir.g ~ an LCO associated with. the Reactor Protection System water level instrumentation. August 1982 Enforcement Conference to ' dis:uss-exceedin an LCO associated wi h' the Vacuum Ereaker g' Alarm System. September 1982 (SALP) hsnagement. meeting to discuss the.results of the SALP for the period September 1,;1951 tg June 30, 1982. ~ August 1983 = A shutican order was issued requiring the licensee to shu:dewn in Cecamter 1553 and ' inspec: the recirculation. system piping fer-Intergranular Stress Cerrosion Cracking. 1: required them to re. main in cold shutdown until authorized to restart by the Director I-of NRR. The licensee replaced the recirculation system piping and was autheri:ed to restar: fr. becam:er 1954 ' Se: amber 1952 (I'LF) Management meeting to discus's the resui s'ef . the SALP for the peried July 1,1982 to June t 30, 1983. November 19E3 Management meeting to discuss refueling /;ipe replacement preparations. January 1984 Confirma:ery Acticn Letter issued regarding licensee acticns relativa to health physics practices following the dis highly. radioactive scur:es covery of small, r:c drive repai.e roem. in the c:ntrol 1 February 1984 Enfer:ement conference regarding the unc:n-trolled handling of small, hignly radioactive scur:es in the c:n:rci r:c drive repair reem., ~ ( l k 1

' April 1551 E A civil penalt problems in c:y ($40,CC0) was assessed fer nnection with the une:ntrolled / handling of small, highly radioactive i' sources in the control red drive repair reem between January'14 and 18,1584 The violation involved ' identified pitblems with the labeling of containers, the use of extremity dosimetry, and the adequacy of instructions given to individuals working _ in the repair recm. L September 1984 Management meeting to discuss a secend-instance of the uncontrolled presence, of i \\ small, hi c:ntr:1 r:ghly radioactive sources in the d drive 'recair r:cm. Oc::cer 1954 Enfor:ement c:mierence en the unplanned ex-- tremity expcsure (within' regulatory limits), connected with the small, highly radioactive scurces in the control red drive repair - rcom. (Follow-up to Sectember IEE4 management meeting en same suhfect) Ccnfirmat:ry Action Letter issued in connecticn with recurring radiatien pr:tection program weaknesses. The letter-outlined licensra plans for evaluating cnd 1 correcting these weaknesses. November ISEA i An order mcdifying the license was issued in c:nnecticn with recurring weaknesses in the racia:icn pr:tect!:n ;r: grad. The ceder re-quired the licensee te c:=plete an independent centPacter assessment cf the radiological c:ntrols program and to submit to NRC review and appreval a Radielegical Impreiement Plan (RIP) for upgrading the i radiological controls program. Follewup inspections conducted in May, August, and November 1925 and April 1956. A Severity Level III violatien (ac civil penalty) was issued for failure to perform ) i radiation surve workers in ac::ys; failure to instruct rdance with 10 CFR 19; and failure to pr:cerly. imolement a pr:cedure in connecticn witn the unplanned expcsure notad above. k Enforcement c nference to discuss weaknesses in the c:n:rel and menit: ring of neu:r:n in-strumentatien during refueling

ert
icns.

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I January 19E5 (5AL?) j \\ Management meeting to discuss tne results of l the SAL? for the peried July 1,1983 to September 30, 1984 Enforcement c:nference to discuss an unplanned occupationni radiation exposure within regulatory limits associated with sludge-lancing operations on a waste tank identified in inspection 50-293/84 44. August 1985 Enforcement conference to discuss lic 1 action on abnormal surveillance test re and a degraded vital area barrier. Oc:cher 1985 A civil penalty (!!0,0C0) was assessed fer the degradation of a vital Area barrier. flovember 1985 ( A safety system function *.1 team inspection I (50-293/85-30) was condseted by the Office of Inspectien and Enforcement to, assess' the operational readiness and function of selected safety systems. The ins;ecticn icencified that the licensee had nc: effec-ively mitigated a water ha=er pr:bler; asscciated with the HFCI turbine exhaus line which had-been occurring since the Ae.cinning_eiplan+%gteration. were also icentified w Ieaxnesses I designihange process;ith the licensee's centivi of plant instr =entatient handling of vender inferma- \\ tien; program for acproving and validating i emergency c;erating prececures; ca i centrol rccm; plant shutdewn from ou;a:ility to conduct a tside the end maintenance prsgram fer meter operated valves. February 1956 Inspection report 50-293/86-04 identified a i severity level III violation for failure to activity radioactive materials. meet pack; This viola- { 1986 by the State of South Carolii ($1,000).resulted in issuance of a civil penalty j ) ( A i

I March 1986 WL?) Management meeting to discuss the results of the sat? for the period October 1,1984 - i October 31, 1925. \\ February - Mar;h 1986 A-special diagnostic team inspection (50-293/ I 86-06) was conducted to determine the under-iying reasons for the' licenset's poor i perfor:.ance described in the most recent SALP and to ascertain whether they could, l have an adverse iapact on the safety of piant operations. April 1986 An Augmented Inspect 1cn Team (AIT) cpnducted an inspection of recent eceratienal events which included 1) the scurious grcup one primtry containment iscia:1cns (and associated reactor scrans), that occurred on April 4 and 12, 1986, 2) the failure of the main steam isolation valves to prcmptly. reopen after the centaine.ent isolations,"and

3) the recurring pressurizatiens'of the residual heat removal sys:am.

The AIT feued the licensee's evaluations felicwing the - second event to be carefully structured and thorcugh. A Confir:natory Action Letter ~ concerning tne events was issued which required the licensee to provide a written ( report prior to restert centaining the results of the evaluation and ccrrective actions. The CAL also recuired Recicnal Acministra ::r aut:cri;:stien fer res:2.. Inscecticn (50-293/86-10) reviewed implementation of the RIP. The inspection fcund the licensee adequately addressed 13 of the 34 items reviewed. ) i May 1986 Management meeting to discuss evaluations and correc:1ve actions c:ncerning the operational events of April 4 and 12,19E6. June 1986 The first in a planned series of management meetings scheduled to review SEco managemene 3 i oversight of the implementa:icn of the licensee improvement programs in pregress. i I t i ( l

\\ Descricticn of Improvement Procram i i i I. Per ermance Imerevemnt P~: cram (SIP) d a) Required by Orcer in January 1922 b) Areas for Improvement 1 Independent Review and Evaluation (MAC) 2 Organization Review /Revisien 3 Management Control System Review / Revision 4) Training'on thanges ~ c) 125 milestenes es:ablished - examcies - Precedure Upda:a Program I (6c0 precedures) - Update Design Dccuments Program (450 drawings) ^ '. d) Status ,C:mplets Licensee.CA verification of final c:=:itment perfor eh Oct:!.er 19E5 II. Radic1ceical Improvement Pr: cram / a) Required by Order in November 1984 b) Areas for Improvement 1) Ince encen: Assessmen: Of Pr: gram 2) Radic1cgical Organization Review /Revisien 3) Radiological Centrols Review / Revision 4) Managemen: Oversight and Corrective Acticns 5) Training en Char.ges c) EC9 Milest:nes Established As of Cecember 1955 cre item remains open (rec:nfigure ac:ess c:ntrol) l I!!. Cen-inucus Imerevem e: Pr:c-tm a) Initiated by SECo in June 19E5 i b) A.tiens 1) Visited plan:s with gecd SALP evaluations 2) C:ndue:ed in:ernal survey to icentify pecbiems/cause ( 3, Issued reper: ef findin;s in Cecem:er 19E5 s l l ) 1 )

.a 7 --l l ~ c) Pr:blem Arecsifdentgffcg; 1) Attitude-Accouncabi11ty. 2) 3) Weak'Rcc: Cause Analysis 4). Ccemunication 5) Effectiveness Assessment d)

5ta tus.

f Ispismentati n ofl sixteen of efghteen racotanendation i rogress E. e e e 9 a e e s O i ( t i ( 1

^ . f p s **c gr UNIT ED STATES o, , y NUCL E AR REGULATORY COSiMISSION .. f WAs HING T o N. D. C. 20$ 55 E ,/ June 18,1986 \\ 1 I J Spence W. Perry, Acting Geners! Caunsel Federal Emergency Mar.agement Agepey Rooru 840 ~ 500 C Street S.W. ~ Washington, D.C. 20472 l In the Matter of Iublic Servi.:e Company of Nety. Hampshire, g a_1,. 1 (Sea'Drook Station, Units 1 and 2) Docket Nos. 50-443 OL and 50-444 OL

Dear Mr. Perry:

In response to a request mede by Edward Thomas of FEMA Region I, we have evalu at ed, !.n conjunction wiith Joseph Flynn of your office, an .undat ed memorandum prepared by Thacias Digna,n,of Ropes and Gray on behalf of the applicants for

the, Seab rook nuclear ple.r.t

("Dignan Memorandum". a ecpy of which is attached Attachment A). Our evaluation is set forth in the fellowing discussion.gs / l T'ne Dignan ?,h!morkndun addresses shat are described as "three misconcep-l tions" pertaining to offsite emergency. planning for the Seabrook nuclear

piant, an d conclu de s thtt they are "f alse as matter of law" (Dignan Memorandum at 1).

Thesc I,urpcric d " misconceptions" are as 'ful'ows: A. That the pitns must be shown to gu arant ee that no adverse ef fec:t s on the public health and safety wili cecur no c.att e r what kind of accident occurs. at S eab rook. B. That it must be deraenstrated that the plans win assure that au persans located Ln the Emergency Planning Zone l or some cer:ain portion of it can be evacuated in some certain ti:ne. In particulcr, there have been assertions that ths plans must assure the sheltering or evacuation of persons from the besches in approximately 1/2 hour. l l 1 It should be note d, however, inat under the Commission's regulations, j g 10 CFR i 50.3, only writtten regulatot y interpretations provided by the Gencro! Counsel w;11 te rect.;gni:cd ss binding upen the Coamiss:!cn. { L\\ g d ,a I;

- _ _ _ - _ _ - _ pence Perry, E:q. a ) g ( C. That 'the plans must be desip v l, and shown to be h-4 e eb;e, to cope with a pariscuW type of accident -- in particular, one kulvin g an . ear!y release of l radioactivity of! die. 1 For the reasons set forth below, it is our ophilon that, with minor eliri-fication, Mr. Dignen's conclusions are essentially correct as to items (A) and g_ d (B) abcve, however, his discussior. Of item (C) appears to contain an. error jg ; which reqLires correction. DISCUSSION A. ,Abroitte Assurance of Perfect Safety. As set forth above, item (A) concerns ti.e questson of whether an errergency n response pisn rnr;t be shown to guarantee that no aciverse health and safety effects, will occur, regardhss of what kind of accident may occur at the phnt. In our c;:Wien, Mr. Dignen correctly concludes that "[n]either the .m Ator:.ic Energy Act nor any regulation of NRC. whether d e e.1hg with emergency plann.ing or not, requires absolute assurcnce of perfect saft ty" (Dignan Memerandum, at 1-2). As yem know, prior to issuence of a full power operating license, NRC re gu-Mtiont. require e find 2ng "that there is reasonable assurance that edequate protective me nst.re s can and will be taken in the event of r raculogical emergency." 10 C,F.R. 5 50.47(a)(1). With respect te offsite mattern, the w r iiR C will base it s Ondin g on a revicw of the FEMA findings and E deterrireiens "as to whetNet State end loca.1 emergency plaqs are adequate F an d whether there is msonsble assurance that they can be implemented.' Id., I 50.47(f.)(2). These regulations plainly do net require any de!Loh ntration of " absolute assurance" that the public will be totally protected in the event of a radiological emergency. Raber, the 'ntant of the Commis.sion's emergency planning regulations is to reduce the ir pact of E an necident an(. achieve " dose savi:igs" through prote :tive actions that' take y Mto consideration pl; int conditions, evacuation times.. absithr factors, anu C cther conditions that may exist at the time of the accident. N U RE G-0654 / FEMA-REP-1, Rev.1 ctatc *. Es (011ews (at 4: The overnlt objective of emerge!..y response pfans is to provide dose savings f and in zone c:tes immediate 11re saving) for a spc.: tam of accider.ts that could produo i ciisite dose s in excess c! Protective Ac' ion Guides (PaGs ). Y The AppenI Board has simi!arly stated, "[tJhe basic goal of emergency planning is the achievement of ncp6. mum desa savings in a radiolodc51 ~ emergency. Cincinnati Gas & Electric Co. (Wm. 11. Zimmet Nuclear Power Station, Onh ICi) AL AS-7 01, T7 N RC T60, 770 (19E3). p_$ ( .m -y (

Spence Perry. Isq.. t in Southern California Teisnn Co. (San Onofre Nuclear Generating Station, Units Tand 3), CLi-83-10, 27 NRC 528, 533 (1933), the Commission unmmarized its rationale for selecting an emergency planning basis as Sollows: The underlying ass %ption nf the RRC's emergency planning regulations tu 20 CFR a ID.47 is that, despite application of stringent safety measures, a serious nu-clear wecident wray occur. This presames that offsite individuals may Ma - r.cntmMMad r,It h g=wg _ative

nnfr-in! ar may be exposed to dangerous levels of ndi-ation or perhaps both.

Planning for emergencies is required as.a prudent Msk reduction measure fer thos:4 individuals. Since a rsnge of accidents with widely differing offsite consequences can be petulated. the regulation does not depend on the assumption that a particular type of accident may er win occur. In fact no specific secident wquences thould be spedfied be-cause each accident could have difiennt consequences both in. nature and deg ec. Although the c1c:gency planning basis is independent of spec!Iic accident se-quences, a number of accident descriptions were con-sidered in development of the Co= mission's regulations, including the corn mit areMent releast cntegories of the Reactor Safety Study (WASH-1400). These.statemen ts demonstrate that the goal of emergency plann'ng is to reduce the impact and achinvc dose sav;ings ter s spectrum of accidents, and that emercency planning may satisfy NRC regulations even though the putetth2 for adverse hcCth cifcett in an emergency has not been tot tny M minated. Notwithstanding c~ur opin!oa thet Mr. Dignan is essentinny torrect in his eenc;usion as to item (A), no statements contained in this portion of his tyamor;.ndum require clarification. Tirst, he goes too far in asserting that

  • it has ' been recognized frdro the outset

. that if cne assumes. a. major 4 accident with offsite releases, some adverse effect nn the pubIfc win, bv definition. v cur (Dignan f.femorandum at 2; carphf.sts added). CantE}y to I leus assertioli'~~the occurrence of a major accident accompanied by offsite re-leases will not naessarily lead to adverse health effects. Rather, in some cimamstances, emergency p!r.nning mey %crue to avert the occurrence.of any ) sdverse health effects. Further, whether any such health effects occur, / and the extent of any such effects, will depend upon a hett of factors, such as the type and quantity of release, the plume direct 3cn. meteorological conditions, exposure durations, and the umely implementation of an appropriate protective response. Secondly, his memorandum sistes ihnt emergency planning is intended to IlmIt any adverse hen!th effcets to as low a level as reasonably pessible.

  • given the facihtias et hand" (Id. ), possibly implying thst adcitional

( 1 l

f Spence Perry, Esq. I t l facilities will never be required to be 1:v!!t or instasted to e,etis fy N/tC emergency planning regulations. In support of this. statement, lHr. Dignan l cites the Fan Onofre decision, supra. However, that decision provides only limited support for this conclusion. There, the Commission addressed only the issue of whirther additional hospital constriction should be undertaken, and concludad that such extraordinary measures are not required. 1 B. Evacuation Within A Speelfic Time Period. The second item addressed by MF. Dignan is whether the Applicants must demonstrate that all or part of the plume exposure pathway EPZ can be evacuated in some speilfied time; in particular, this item addresses the question of whether the beaches in the Seabrook vicinity must be evacuated within approximately one-half (1/2) hour. It is Mr. Dignan's conclusion that l NRC regulations do not require that an evacuation be assured within any particular time (Dignan Memorandum at 2). We concur with Mr. Dignan's eenc3usion as to this item. In support of his conclusien on this v.atter, Mr. Dignan cites two decisions: Cincinnati Gas a Electric Co. (Wm L fimmer Nuclear Power St ation, U nit No. 1), AL AB-727, 17 NRC 760, 770 (1953), and Detroit Edison Co. (Enrico Fermi Atbmle Power Plant, Unit 2), AL A B -7l10, 17 NRC 1057, 1069 n.13 (1983). In Zimmer, the Appeal Ecard" stated as fouows: The applicants are . correct in their insistence that the Cornmission's emergency planrdng requirements do not prescribe specific time limits governing the evacum-tion of plume EPZs. The matter of the time in which evacuatien can be scrcmplished is left to be determined a case-by-case basis upon consideration of all rele-on vant conditions prevailing in the specific locality. Eut J it does not fcDow, as the applicants would have it, that I a particular evacuation plan need not be concerned with the efficiency with which evacution might be accom-plished give.n t.he conditions under which it must take place [n. 161 Indeed, the Commission guidelines sug-gest the contrary. If the responsible govern-mental officials are to make an informed decision respectin g what is appropriate protective action in a given radiological emergency, they must have available to them time estimates which are realistic appraisals of the minimum period in which, in light of existing local conditions, evacuetion could reasonably be accom-plis he d. And, the nearer to the plant the area that might have to be evacuated, the greater the importance of accurate time estimates.

n. 16/
  • inese conditions include, for example, the si:c and nature Of the population,

the available

Spence Perry, Esq. transportation fa cilities, the existing road net werk, topographical features and political boundaries. Zimmer, supra, 17 NRC at 770-71. Similarly, in the Fermi deciclon the Ap-ped Board stated: q i [T]he Commission's emergency planning regula-tions do not specify the time within which the plume EPZ must be evacuated in the ev,ent of a nuclear emer-only that applicants provide *an analysis of the time l gency. 10 C.F.R. Part 50, Appendix E, 5 IV, requires j regtdred to evacuate and for taking other protective J actions for various sectors and distances within the plume exposure pathway EPZ for transient and perma-nent populations." Fermi, supra,17 NRC at 1069 n.13. Thus, there is no requirement that an ' evacuation ~ be accomplished within 30 minutes. While some other functions i must be capable of being accomplished within that time frame, those functions g enerally involve the notiScation of appropriate governmental of5cials and notification of the public. ,See,10 C.F.R. Part 50. Appendix E, f IV.D. C. Planninc for A Particular Type of Accident. The third hsue addressed by Mr. Dignan is whether a facility's emergency plans must be designe d to cope with a particular type of accident and, in j particula r, an accident involving an "early release of radioactivity off-si.e." Two conclusions appear to be reached by Mr. Dignan in th*is reg:rd: (1.) that while emergency plans must be designed to cope with a spectrum of f accidents, they need not be designed to cope with a speci5c accident or "an y worst case accident" (Dignan t.iemorandum at 4), and (2) that emergency plans are not required to be designed to cor a with an euriy release of radioactivity (Id., at 1-3). While we agree with she first of these conclusions, the. second. conclusion is incorrect and requires clarification. First, t.1r. Dignan is correct in stating that the emergency plans must be de-L signed to cope with a spectrum of accidents, but are not required to address any particular accident sequence or a "werst case accident." The Commission has d ecided, on a generic basis, that compilance with its emergency planning regulations provides the reasonable assurance required by 10 C.F.R. S 50.47(a): accordingly, offsite emergency plans are not required to address particular accident sequences. In the Statement of C6sMeration published upon adoption of the Commission's final emergency planning regulations, the Corumission stated as follows: The Commission recogni:es that no single accident scenario should form the basis for choice of notification ( capability requirements for offsite authorities s.ud for

Spence Perry.Esq.,..., the public. Emergency plans must be developed that will have the hexiblUty to ensure response to a wide spectrum of accidents. This wida spectrum of potentid accidents also reDects on the appropriate use of the offsite not!Scation capability.... Any accident involving severe fuel degTedation or core i melt that - results in significant inventories of fission. products in the containment would warrant immediate 1 public notificeflon and consideration, based ori the l particular circumstances, of appropriate protective l action because of the DMential for leakage of 113e con-l tainment building. In addition, the warning time avail-l able for the public to take action may be substantially less than the total time between the original initiating { event and the time at which significant radioactive re-l leases take niace. The reductisn of notification times frot5 the several hours required for street-by-street noti 5 cation to minutes wilj algniScantly i inerense the options available as protective ections un-9 der severe accident con ditions. These actions could include staying indoors in the case of a relen::e that has already occurred or a precaution'ary evacuation in the case of a potential release thought to be a few hours away. . Accidcnts that do not result in core melt may also cause relatively quick releases for which protective actions, at Icast for the pubuc in the immediate plant vicinity, are desirsble. 3 45 Fed. Reg. 55402 (1H0). Simi:arly, NUREG-0654 / FEM A' Rep 1,

Rcv, 1,

4 provides as follows (at 6-7): No single spec!De accident sequence. should be bolsted as the one for which to plan because each accident could have different consequences, both in nature and de gree. Further, the range of postible selection-for a planning basis is very large, starting with a zero point of requiring no plannt:g at all because significant off-aite radiological accident consequences are unlikely to c,ccur, to planning for the worst possP;1e accHent, re-gardless of its extremely low likelihood. The NRC/ EPA Task Force did not attempt to define a single accident sequence or even a limited number of sequences. Rath-er, it identified the bounds of the parameters for which planning is recommended, based upon knowledge of the potenti 1 consequences, timing, and release characteris-I tics of a spectrum of accidents. Although the selected i f ple.nning basic is independent of specific accident se-quences, a number of accident descriptions were con-cidered in the development of the guidance, including i 1 1

____q b I . Spence Perry, Esq. j j I 's 3 the core melt accident release categories of the Reactor Safety Study [ WASH-1400), Accorck Car Onofre, supra, 17 NRC at 533. In Long Island Lirhtine' Co. 1 ~ T6fio* raham ifuclear Power Station). LEP-8S-12, 21 NRC 503', 8'f 3 G9d) (cited L Sn Dignan Memorandum at 4), the Lietnsing Board dismissed a contentfon ~as-co ting that the emergency plans must be capable of coping Mth any' wo st cat,e accident (there Invbiving the possible Ioss of offsite power); the Board ~ stated, 'NUREurC654 dres not require an adequate response for the ' worst possible accident' nt Shoreham. In

sum, these regulatory 3

pronouncements ed decisions clearly demonstrate that emergency planning for a nuclear plant is not required 16 be designed to cope with any i particular accident vsquence oe a verst case accident." in this respect, we i a f;oncur with Mr. Dignan's memorandum. The Dignan Memorandum is incorrect, however, in its conclusion that the i emergency plans are not required to be designed to cope with an early release of radiosciivity (Dignan Memorandum at 2-3), This error appears to have resulted by confusing the " worst possibie accident" for any accident b4volving an eerly rolesse. While the " worst possible accident

  • could involve an early releese of radioactivity, other less severe accidents might also i

result in early releases and were included within the para. meters which established the Commiss4cr.'s emergency planning basis. The Statement of ( Consideration, quoted above, clearly recognizes that *early releases" may eccur; it is for this reason, in part. that the licensee is required to notify i offsite t.uthorities within 15 minutes after the licensee has declared an emergency, and that responsible offsite authorities have a capa bility- .t o l notify the public within 15 minutes after they have received notification from the licensee of an emergency cond!!ien. The following guidance is provided in 'Nt' REG-0654/ FEMA Rep.1 Rev,1 (at 13-14): ) The ra.nge of times between the onret of accident condi-tier s and the start of a major release is of the order of one-he.lf hour to several. hourso The:subecquent time ~ period over which radfor.ctive cisterial may be expected to be released is of the order of one-half hour (short-inrm release) to a few days (continuous release), (G)uidance on the time of release..... has been used in developing the criteria for notification capabilities. (Oth2r reasons for requiring prompt notification capabiHties include faster moderate releases for which protective actions are desirable and the need for sub-stantia.1 lead times to carry out certain protective mes-ryres, cuch as evacuation, wnen this is indicated by plant conditions. ) it should be noted that the responsible offsite. authorities are not necessarily required, in all cases, to notify the pubuc within 15 minutes after they have ] E_ _ l

i spence Perry, Esq. I_ s p 3 received notification by the licensee. Rather, the time in which the public le notiSed will range from !mmedfste notification (within 15 minutes after state and local officials are notifies!. thgt a situation exists which requires likely fevents where there is substantial time urgent action) to the more a f ailable for them to make a judgment as to whether or not to activate the i public notification system. Also, it should be noted that the 15 minute criterion refers only to the time in which the pub;1c is to receive notification, and does not refer to the time in which protective actions are to be completed; In sum, responsible offsite authorities must have received notification of (1~.e emergency situation within 15 minutes after the licensee has declared an emergency, and the offsite authorities must have the capability to notify the public within 15 minutes after they have received notification from the Ifeensee.. Emergency ' planning for accidents involving "early releases" is required -- although the protective action recommendations may be issued be fore, during or after the occurrence of an offsite release of radioactivity. There,is no requirement that protective actions be completed within 30 minutes after the licensee has declared an emergency. CONCLUSION For the reasons set forth above, the foUowing conclusions are offered as to the matters referred to in the Dignan Meicorandum: i 1. The basic goal of emergency planning is to re duce thr impact of and achieve dose savings for a s p ectre. of eccider.t s :

however, therc is,

no requirement that absolute assurance be provided that adverse radiological effects will not occur. 3. The Commissicr.'s emergency planning regula-tions do not require that the evacuation of all or part of a plume exposure pathway EPZ be completed within any particular time. 3. The emergency plans must comply with the Commission's emergency planning regulations and there-l by should be capable "of responding to a wide spectrum of eccidents; however, the plans are not required to be designed for any specific accident sbquence or a " worst case accident." \\

Spence Parry, Esq., \\ 4 4. Accidents involving early releases are within the Commission's emergency planning basis, however, the regulations do not specify a. time within which the recommended protective actions are to be completed. Sincerely. Edward 5. Christenb[ Director and Chief Hearing Counsel Enclosure ^ cc: J. Taylor E. Jordan T. Murley ) f S 9 1 _2_m_ _ _ _ _ - _ _ _ _ _

MEMORANDUM This memorandum addresses three misconceptions which have arisen as to the standards to which state and mun:capal emergency plans will be held in an NRC licensing proceeding, These misconceptions.are: i -A. That the plans must be shown to guarantee that no adverse effects on the public health and safety will. occur no matter what kind of accident occurs 1 at Seabrook. B. That it must be demonstrated that the plans'will assure that all persens lecated in the Emergen:y l Planning Z:ne er s==e certain pertien of it can be 1 i evacuated in some certain time, l t In particular, there have been assertions that i the plans must asture the sheltering er evacuat::n ci pers:ns f r e.. the beaches in apprcxinately 1/2 heur. C. That the plans must be designed, and s.'own te be i able, to cepe wett. s particular type of acciden: in particular, one. involving an early release of radioactivity e f f-site. Each of these preposittens is false as a matter of law. First, the issue of absolute safety: Neither the Atomic Energy Act ner any regulatten cf NRC, whether dealing with emergency planning or net, requires absolute assurance of ( t

l 1 perfe-t safety. Indeed, it has been recognized from the -outset of the formulation of the current emergency plann:ng q regulations that if one assumes a major accident with i offsite releases, some adverse effect on the public will, by i definition, occur. The purpose of emergency planning is to have in place means and methods of coping with such an event i ~ in order te keep those effects to as 1ow'a level as j reasonably pessible given the facilities at hand. Southern California Edisen Co. (San Onofre Nuclear Generatsnq Station, Unt:s 2 and 3), CLI-83-10, 17 NRC 528, 533 (1963). Secend, as to the prcpetition that the plans must be demonstrated.:e he capable cf assur ng evacuar:en of certa:n areas within a certain ::=e: This s:= ply is not the law. The Appeal Boards of the Cemnission have so held - flatly and withcut equiveca zen. Cine:nnati Cas & Electric Cemeanv .c er 5:stien, Un:: No. 1, ALAS-727, (Wm. H. Z:- er Nucle 5r 17 ::RC 760, 770 (;?E ). T r. e Ce r::: Ed:sen Cc (E..rico Term: Atemic Power Plant, Unit 2). ALAS-730, 17 NRC 1057, 1069 n.13 (19E3). Indeed. the enly activity which the f regulations specifically require te he capable ef-accecplishment an ene-half hcur is public netifica:icn. And it is in that centex: the 1/2 heur ' rule is discussed in NUREG-0654, the NRC energency planning guidance document. Third, the p r c p e r : :: e r. tha: the plans will be Judged as to adequacy agcins a certa:n type of accident and in particular ene invclv:n; a release as socn as 1/2 hour: \\ a g ___________O

That preposit:cn to nc*. only bad law, it 1s_directly contrary to the theory of the NRC emergeticy planning ^ criteria. The thcory upon which the regulations we_re based was that the plannerr should consider a' spectrum of ac cide r.t s. The key is that the plan be shown to be flexible and capable of reducing the adverse effects to the greatest i extent reasonably possible. The commissinn itself has stated: "Since a range of accidents with videky diff ering offsite consequences can be pov. slated, the regulation does not depend on the assu=ption that a particular type of accident may or vill eccur. In fact, no specific accident sequences shculd be sp&c f:W4 because each accident ceuld have different consequences both in nature And degree. Althcugh the emergency planning ba sis is independent of. spec:fic accident f, sequences, a r. umber of accident descr:priens were considered in development ef the Commise n's regulatzens, includ:nq the core melt a:c: den release ca:eger:es cf the Ee a:::r Ea f e ty Study (WAEE-1400 ). "It vis never nhe intent ci the regulatien to require directly or indirectly that state and lecal governments adept extraord: nary eensures, such as c=nstruction of addi enal hesp:: mis er recruit =en: et substantial add:::enal medical persennel, just te deal with nue19ar plan; accidents. The emphasis is en prud e nt risk reduction measures. The regulatten does not require dedica tien of resources to handle every possible accident that can be imag:ned." CLI-ES-10, 17 NEC a: 532. 4 e 3 1 I i 1 ,___________.__-J

i y + =. l o. = '~ h h-Further=cre, there is.no requirement.that-it be e .J I -demonstrated that a plan will cope with any worst case l accident. NUREG-0654 simply does not require an' adequate response for the worst possible accident. Lene Island j Liehtine Co. (Shoreham Nuclear Power Station), LBP-85-12, i 21 NRC.603,'888 (1985). In short, the standard by which any emergency plan is to be judged is whether er net it represents the best effer:s of knowledgeable people through-the use of reasonably l available facilities to reduce to the maximum extent reasonably pessible the. adverse ef fects on the public health and safety wh:ch w ll result frem off-site releases result:ng frem a spec: rum cf ace: den scenarios. The guiding principles, as recently stated by an NEC Licensing i I Soard are: "The purpcse c f emergency planning is : achieve dese sav:ngs te the general publ : in the event that rad:cactive i ac': dentally released off material'is c s::e. .There is no min:=um standard cf public radia::en dose which must be me

n emergency planning.

l i ".bsolute protec:len ci the public ? against all radia::en ecses canne: he' guaranteed and is not required for all i possible acciden scena-es. l "The emergency response plan should not be develeped for any specific preconceived accident tequence. It l should instead be framed te cepe w :h a spectrum of ace: dent pessit:11 :es l

n:1uding the vers: ace: dents.

t 1 ,(- V. l -4 t -m_-____

"There is no standard t1me requ2 red to be '.., n t for evacuation in a radiological emergency. Estiir.ates are necessary to deterr,ine accurately the actual tIEe reqc red for evacuation. These t e s t:..at e s are needed to aid in protective action decasierzaking. "No massive investment of resources (stockpiling oi supplies or construction of hespitals) are required for emergency planning. He vi11 appiy a ~ ractical p standard of efficience of utilization of existing resources (such as roadways and I manpe% r } in evaluating the acceptability of the evacuation plan. " LBF-S5-12 at 782. h a ( t e t 5-

7

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UN!TE D STATES ji ) NUCt.E AR REGUt. ATOM COMMIS$lON c-uswiwtow.o. c. ross> g .s y October 7, 1986 1 LICEt. SEES : ELE OW.'.Et!+ c;;0t p FACILITIES: /,LL En rtAt:75 St: EJECT: SLE A:Y 02 SETT[FEEk11,'19EfFTCTIldOhCEfiEr.:C RECL'I AEMEti:5 F0F %k C0fiTAllMf,T1 i

t. c+etir t tetweer the CWP Cwerrs ' Grct; Cethesdt,i:aryler.c, cri Se; tert.er 11, 19EC.(E'JC.C) ar.c the !?FC has hele ir u

Tr.e pLrpc s.( cf the tr.eetir$ ha! fcr th! KFC-Ic presert tc tr4 E 4 CG a se: cf str6wir.ar. gereric requirer +r ts t'e r. cctricered b.r tra liTC & tre pLepcse cf enher.cins SWR cor.tainter.t perforvar;.ce in severe acticer. cencitic ri. The CWROG was te present the ranits cf its ptrailel stucy esirs I;crtrert itate! Pewr

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ite fcr :.cvere:gr , ;Hf. 4 /, VCha'. C. Thacari, Frcject Ya sger Ger.eric Rec;Literer:s for EWF Coritzintner.ts Er41cstres: Is sittet R E C i g 'i -- 3, 1 l' cc: %/erclCsLrei: See ces* Iacts DCT1 4 M_o, E. P. J. i Q i

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Enclosure f1> NRC-BWROG MEETING ON CONTA:hMEhi REQUIREPEhTS l SEPTEP.EER 11. IS86 s 'NAME AFrILI ATION R. Bernero NRC/ DBL H. Denton NRC/NRR .C. Reed Commonwealth Edison John Asu1ston . Tennessee Valley Authority Vincent Beyer Philadelphia Electric Company Richard Diederich Philadelphia. Electric Company James C. Carter IT Corp /IDCOR Edward Howard Boston Edison } R. E. Skavdahl General Electric Johr.. F. Fultun boston Edison Corean; T. H.1.ande rs New York Power Authority J. A. Grey, Jr. New York Power Authority S. D. Ficyc Carolina Power & Light Compary A. P. Cutter Carclina Power A Light Company H. W. Aesst. Perrsylvaria Power & Light Ccesar;. Eriar EcCa'frey Lets Islar,d Liget1r.g Ccepany Charles Caveric Lor 5 !sland Lighting Compar.y L. T. Gutwa Gecrgia Power Cor. par.y S. h. Chesrct Georgia Power Compary j J. R. Langley Gulf States titilities/HCOG Terry Pickers horthern States Power Kevir. Fcit: claw Gereral Electric Company Dear hcuster hRC/ACRS Staff Farcul Eltawila hRR/CSR0/RIE J Jir teocers Gt.'.f States l'tilitits Cet;ar; Dernis E. hactirs .Enercon Services /hCOG Wayr.e hocces hRC/ DEL /RSE L. G. Hulrar NRR/ DEL /PSE Ar.gelc F.a r t re s NRR/ DBL 'S. W. Wilczei, Jr. Niagara Mohawk Bruce A. Pres:cr Power Supply & Ergineerir.g & Ccr.s* i Richard F. Mv ay Power Supply & Engineering & Const. { Pichael J. May Tennessee Valley Authority - BFh 1 Woody Stroupe Enercon Services rat Pcwell Washington Public Power Supply Syster. Lynn Conner Doc-Search Associates Larry Gifford General Electric John Stang NRR/BWRd/ Lacrosse Project Manager thor.as S. Retella NRR/ DBL /BWDa Big Rcck Fcint Pf' Rar.an Pichur.ari NRR/ DEL / FOS Donald R. Heffear Cleveland Electric 111urinat1r.s Vernon 1.. Recney NRR/ DBL /BWD2 John Larkir.s OCM/LZ Kazimieras Carpe NRR/ DEL /PSB berald E. Gears hRR/ DEL /PDr2 ? k

i ] 7' KAXE AFF1LI ATION l i Jack Kudrick NRR/ DBL /PSB l Jay Thayer Yankee Atomic R. J. Lodwick Vermont Yankee stephen P. Scheltz Vankes Atomic Electric David H. Wagr.er NRR/ DBL /8WD3 Domenic B. Vassa11c NRR/ DBL /FDB i Daniel R. Nuller NRR/ DBL /PD2-John A. 2woliptki NRR/ DBL /BWD) { Raj Auluck NRR/ DBL /BWD1 Jack Donchew -NRR/ DBL /BWC2 E. G. Adensen NRR/ DEL /BWD3 Earl Page Detroit Edison Phillip L. Paull Vermont Public Service Dept. G. Tarrant VT Dept. Pub. Service N. W. Edwards NUTECH C. L. Reic' bechtel Dwer M. Sect: Southern Co. Services G. C Leir.as NRR/ DEL Eve fetcp:cle SERCF Licensir5. Etchtel Akira Drr:c The Tckyt Electric Pcte r TetsL 1r TEF:C Seng Ec U. hER/CEL/PSB ) P. char. C. Tnederi hRR/ DEL /BWO2 t Kathleer F. Snet hewmar. & Holtzinger J David Wilser Iowa Electric Lig't and Power n Stepher. Melcre, Devenrue Ccr. Lewis Ptssissippi Power 5 Lignt Pac 1 Lee:r NRC/EWC. 1 1 e l l 1

c,. 3 ~ '.t' 3 p. i ) I ) 1 1 o i 1 ,l" DISCUSSION OF A-1 1 GENEF.IC LETTER ON i f E,n,n_ CO._A e, h,M h.T P:.nr0RL, h,.-: u a .I c...., t S:.: i _:v_::r. 1.1, Lo.c.:. ^ f R03ERT M. BERNER0,.USNRC i 7 e k o ,s..... (_ . _ _ _ _____....____.___._.___________i

m a I w 1 N s .i GENERIC LETTER ON Eh'LCONT4iNMENT PER:0RPfNg i 4 l 4 7 u r g :. T i. i..>.. p..Ai.., tyn tit.tr,i.c g.i..,r.'. TF.. S V.P. A F.C ] B..'. '~. P.'.'. I C Y w .w. .r g. r, .r..,,:.. - ..a. l t 7 c.. :. y. r. v p : _.. : i. n. i;. c'.. 1:.. A '.' ' C ' '..:.'- 4" .l TH: SU5)EOS: 37 Eh'RS h'ITH FRESSURE FJP: ESS10N CONTAIN".ENTS TFE METHOD: A GENERIC Lt.:iER 0.: REQUIREF.ENTS TO ltP' EMENT CHAN3ES BASE.D ON GENERIC EVALUATION l s i r< p 1

...- t.. :/n., s. e. r.. IPE FDE :RDNT EN.: MAY REICE IUT N' CREDIT IS TAKEN HIP.~ s e CCNTA:N.E.;T C'?AI:L'TY: SUEITA.;TJ AL ASSURAff'E THAT " r~. ~ C r. *$ r *. '.1 '. ~. 'i i' ' ' '. ' - h' ' 8 i I. . ' 0 . '. L L" 'C'; y ".l *.b~ ~ r~. 5, ; 0. ;*,.~ ~ c - \\' r' f'..' M' '~.e'. ^ -~~ ~ ~ f L ~ r .u e... 3,i k,, b. A r h J r. g r ,..(.. 4 L' r t e. a ; &wi J L,,v s,.r" DU LUr.; l'.r.L i e., - m. e,,..,.- L ,l' r.,. h Il l v. c. v Ll '. s 3: B : D...* 0 ;h a h l 'J '\\ e17 eL

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r,. .-A', t HYDROGEN :0NTROL - ) PR000 SED REQUIREMENTS-w CHANGETECH, SPEC.ATENDOFOPERATiONFROM24-HOUR e ALLOWANCETO12-HOURI.V.0WANCEOFNDH-INERTEDONERAT REDUCED POVER PERMIT 12-HOUF PERIOD AT REDUCED 90h'ER WITHIN THE OPERAT e CYCLE TO SEARCH FOR UNIDENT!?!ED LEAKAGE E!* : D'.: J LEINEniifd TYF C'LLY TAl:E5 4-E HCL'ES o- - -... e 3.....,. .. r. r.:.. A.. C a,,i e., r.:.. an:.. 1.,...._, M.fs... . r.

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. :r. i w., r i. e A'H EVED IN 4-E HOURS REDU:E; POWEF, (6 33n SL'ESTANTI ALLY REDU:ES SH5ET-LIVE: e FISSION PRCDUCT INVENTORY AND DYNAMICS OF PCSSIE.E AC i I l (.

DDYWELL SPRLY ,.) PROPCSED REQUIRE".ENTS .i. e REDUCE DESIGt; SPRAY RATE (CHANGE N022LES) TO ABOUT 30; 0F l-I PRESENT VALUE e PROVIDE AC-POWERED EACKUP WATER SUPPLY FOR SPRAY AND AC-INDEPENDEN WATER SUPPLY, AVAILABII.1TY BY REF.CTE P.ANUAL OPERATION OR BY S!P.PLE REL1ABLE PnCCEDUP.E i DES!; E'.E e F.AME ALTERNATE WATER S 'JECES AVAILAELE TO C03; CDRE LIEE:T.Y t i s 9'/;0 F.:DE 0? EHR OPER; TIC:, t W 1 C'. : '.E l - e WATER SUFF ]ES AO ECL'!PP. INT ARE ALREADY AVAILAELE F0F. LOWER 1 FLOWS e LOWER. FLOWS PROVIDE ALL EENE?!TS EXCEPT LOW 4 T DECAY HEAT REX 0 VAL AND DD NOT RAPIDLY FLODD CONTAlh'"J.NT l l e ASSURED DRYWELL SPRAY SUBSTANTIALLY REDUCES PR;EAE!LITY Afs-SIGNIFICANCE 0" DRYWELL FAILURE OR SUPPRESS 104' F001. EYPASS ~ t 4

20 PRESSURE CONTRCL PROPOSED REQUIRE".ENTS RELIABLE CAPASILITY TO VENT WETWELL AT EPG PRESSURE LEVEL e WITH'OR W1THOUT AC POWER. FOR VENTING WITHOUT AC POWER MAN'JAL PROCEDURE IN ADVANCE MAY EE USED ?F N!TROGEN PURGE IS AVAILAELE e' VENT OF JS-IN:H DI AMETER OR GREATER DES ! c:? '. E AE:L:TY TO VENT SLC'*:EF SE0'JEN:ES THRDUGH STAN:EY GAS e TREITMENT SYSTEM g., g.p.p.p.>7:- , 7. -. ~ e, *. c.:.r.. : u r L e,,<... 4. : L.. p q. c

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e COMPLICATIONS RATIONALE RELIAELE VENTING PREVENTS UNCONTEDLLED OVERPRESSURE FA! LURE e WHICH'CAN CAUSE CCF.E MELT I VENTING WITH DF.YWELL S?F.AY GIVES GP. EAT ASSURANCE OF RELEASE e MITIGATION 9 1 u____________ l

1 CHRONOLOGY 4 9 e JUNE 26, J985'. MEETING WITH BWROG/IDCOR PROPOSED A GENERIC i LETTER, PRESCRIPTIVE SDLUTION, BY BACKFIT i 3985: VERMONT YANKEE COMMITS '20 GOV. Kuh'1N TO DO A e ' JUNE 30,60-DAY CONTAINMENT STUDY SPECIAL e JULY 25, 1985: BOSTON EDISON COMPANY BOARD DECIDES TO F1X PILGRIM CONTAINMENT ~ AUGUST 19,1985: BWROG EXECUTIVES VOTE TO FUND AND CONTIN'JE e DIALOGU: ON THIS WITH NRC, CONTACT NUMARC AIJUT BWR VS PWR e SEPTEM3ER )), 3985: MEETING WITH BWROC TO COMPARE BACKPIT l' NOTES AND STRAWMAN GENERIC REQUIREMENTS e SEPTEMIER }}, 1985: MEETING k'lTH VERMDNT YANKEE TO REVIEW CONTAINMENT STUDY e SEPTEMIER 23, 1925: NR:/IDCOR MEETIN3 ON BWR/ MARK 1 ANALYSES i e SEPTEM3ER 23, 192E: ACES SSE:0".TTTEE ON CONTAINMENT PER:0RK;h:E TD CISCUSS FAR:ERS FERRY WDRKSHOP RESULTS AN EWF C0hTA!NMENT GENERIC APPRCA:h SEPTEMEER 24, 1925: ACES SOECOMMITTEE ON CLASS 9 ACCIDENTS TO e DISCUSS EWR/ MARK J ANALYSES AN;' SEVERE ACCIDENT PROGRAM 25, 3935: C:GR REV'E' 0F ER*:T GENERIC LEU ER 0., EW:, N:VEMIER s CChTAiN.ENT RE:.!EEMENTS (TO EE FUELISHEL FOR COMMENT) DECEMEER 27, 3935: ISSUE DRA:T GENERIC LETTER ON SWR e CONTAINMENT REQUIREMENTS FOR PUELIC COMMENT e A RIL 1927: ISSUE FINAL GENERIC LETTER ON EWR CONTAINMENT REQU1REMENTS i j i (

.u .4. 1 e-CORE DEERIS g es ' P PROPOSED REQUIREME'.~, e.. m y. ~* e ASSURE RETENT10N OF WATER l' LEAST 3 FEET DEEP IN TORUS RDDP. ,. n. IF TORUS LEAKS ENTIRE CONT. TS l l w ..C DESIR A3' E + . (,. i e CON: RETE CUEIS OR OTHEF 3/EE!ERS WHICH WOU'E RITARD DEER:S A", Iu' ' K 0.: D.W...'.'..C...'.'. i~ s. ( AV0]D LOSS 0: RECOVERY SYSTEMS FROP. WETTING EY TOR'JS RD:". N..

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C0!i:LU510NS - BWR D:ECUTIVE MEETlh'G ( A' 3UST 19 MEETih': - 20 0F 23 BWR03 UTILITIES REPRESEN J o C0liTINUE CONSTRUCTIVE DIALOGUE WJTH NF.C o o ASREEMEl;TS: C0"luT TD IMPLEviliTAT10N OF REVIS10f; 4 TO EP55 li'f, ARC C0!;TACTED TO CO ulDER SEVEF;E ACCIDENT C0; tai!"' INT ISSUE AS A GENERIC INDUSTRY ISSUE C:'J:!;.'E W:n::h'c W: TF fi:.: TOEETTEFDE:!;E!!!.'k:

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I The f ollowing materiai was provided by Mr. Joseph Bernero, j Chief of the Boiling hater Resetor Div2sion of the NRC. "' severe accidents' is the term most commonly used to describe l accidents in which the reactor care is severely damaged.. As happened'at Three Mile Island, prolonged loss of core coolina ) can allow:the; heat of radioacti ve decay on t'ne core to build up to the point that the fuel begins to disintegrate, the o zirconium. metal cladding melts or reacts with residual steam te form conbastible hydrogen, and even the ceramic uranium oxide fuel pellets can melt. A great deal of attention is being given to understanding the behavioi> of reactors and their containments in severe accidents, especially since the Three j Mile 1sland accident. The objectives are to ensure that the I likelthoci of core cal' eceidents is very low ind that, shculd ene c cc u r ', Ih. re is s u': s t a n t i a l assuranct

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] will mitigate its' consequences. 4 The severe accident behavior of a BWR w:th a Mark I i containment, the Teach Botton Plant, was assessed in the reactor Safety Stuly (hA51:-14 C C o r NUREG

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r, .st S t u.! y i n.f i c a t <r d a r>1ativaly )".e c r e r.a l l risk for the B'.G, principally Jue to its ability te prevent core melt. The containment.was estimated to provide very little mitigation of core melt consequences because the { buildup of.preature under accident conditions would be a direct { cause of containment f ailure unless adequate cooling was preserved. Consistent with operating procedures in place in 19 5, the Study assumed little effort by the reactor epefcators which might effectively preserve the containment's integrity. l l k l i I .___________- _ _ a

t 7 i The' situation. more than ten years later,. is differe;it and still changing for the better. It is recognized today that mciten cere material melting into the ground through the thick containment base is not the principal t h rer,t ; rather, it is an atmospheric release of radioactive material which is the principal. threat. The principal factors which can cause containment failure with atmospheric lelease are hydrogen ignition, gas overpressure buildup '<c rupture,-and direct attack of the dryw611 by core melt debris. The general situat' ion for each of these is summarized cc follows: Hyd ro g en Ignition ' recognizing that combustible hydroges car; be generated cnd - r t l e a s e.' in severe acci4 ants, oil Mark'I ctmtainnents now are purged and fiiled with inert nitrmgen gas during eperatinn so that even if hydrogen gas is fc:med it has insufficient oxygen availabic to support combustion. Remaining questions in this area relate to how long the containment may be without this - i'nert atrosphere in order to permit inspections, and how air might lesh in or hydrogen leak cut to nearby rocrs undtr . ? n.i. '. I

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l I \\ '.0verpressurs F ilure Careful analysis indicetes that a typical Mark I containment can withstand pressures bf more'than twice the design pressure without rupture. Nevertheless, severe accidents in the extreme ccn generate such pressures and cause coM einment rupture. Overpressure damage control procedures have been develeped for pressure s'uppression containments and are already in place for optrator use. With the.e procedures the containment remains closed for most accident conditions; tut, if overpressure failure threatens, large vent valves above the supp*cssion pool chamber are opened so that the excess pressure is i' released gradually by bubbling the releases through the pool, forming a filtered vent containment system. With this path assured, virtually nothing S but f.he noble geses are released. The radioactive noble gases pose a modest expcsure threat of fsite only in the crea very c1cse to the plant. A number of questions are being pursved in this area. Ali the f.lants have suitably la ;e 1 l vent valves anc c cts cut t.ey very cre to another in the ability to (men these valves under accident conditions. The valves are designed for hignly reliable closure, not opening. Cor. sideration is being given te modifying valve controls. In addition, the vent ductwork downstream of the valves may .< arrant modification. In most plants it is fairly light gauge auctwork and mig ~.t be breachec in accicent venting. If so, consideration is being given to the effects cf secorda y reiesse of radicEctive gas, hydregen, and pE.*ha?s stcam int 0 thc reacter building. Direct Attack The core m91t cebris, since it has melted through the reactor vessel into the drywell mhy, by direct radiation of heat, cause failure of connections in the drywell shell; or the debris, if suf ficiently fluid, may flow out to the wall and melt through the steel. The Park I containments have one or more spray systems in the drywell which are a:le to spray water along the walls and onto the floor of the drywell inhibitir.g direct atteck. Concerns in this area are in three general treas: core debris modeling, shell and concrete attack modeling, and spray reliability. In the first area, it is recognized that a molten reactor core, to melt through tM bottcm of a BWR, cust dissolve a very

large & mount of inert rnetal in the lower reactor vessel, probably diluting the ire ceit. The key question is whether the melt would come out moving . sluggishly like Hawaiian volcano lava or as a hot free flowing liquid. The latter is the more threatening condition. If core melt debris reaciics the cone. rete floor and steel shell of the well, it is important to understand thei the path to the outside that might be opened bypasses the beneficial scrubbing of radioactive material passing through the ) pool. As noted earlier all these plants have drywell spray systems, but they c.re designed as a secondary mode of operation for a reattor safety system. Strong i consideration is being giuen to enabling hookup of these systems to fire protection systems so that spray capability is almost always avellable. Substa.tially dif ferent emergency cperating procedures and training are put in place at.all reactof s af ter the Three Mile Island eccident; fur;< fr dmprevements in these procedures are still being made. For the Mark I ontainnents both industry and NRC studies are beir.g used te identify the test ccebined strategy fc.r procedcres and perhaps seme changes in equipment such as alternate vent paths, or irpra.ed vilve operability. The Ma-k I studies are being given hignest priority by the HEC staff and the ind.istry. The ' expectation is that, with ecdest improvements of this type one can achieve substantial assurance of core melt consequences mitigation by 4 Mark I Containment. _ _ - _ - _ _ - _ _ _ _ _ _ _ _ - _ _ _ _ _ _}}

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