ML20040B807
| ML20040B807 | |
| Person / Time | |
|---|---|
| Site: | 05000000, Limerick |
| Issue date: | 10/21/1964 |
| From: | US ATOMIC ENERGY COMMISSION (AEC) |
| To: | US ATOMIC ENERGY COMMISSION (AEC) |
| Shared Package | |
| ML20040B769 | List: |
| References | |
| RTR-WASH-740 NUDOCS 8201260428 | |
| Download: ML20040B807 (11) | |
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MIGUTC CF ST~. :I.:G C^.' *.!TI- C': R C, ISIC:: CI' '.:ASil-710 AT BCOOl31AVC: I:ATIO::AI. L/J'.OPJ.K 'J!, OCTC3JH 21, 1964
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R. L. Doan, /.C -DRL
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M. J. l' Cool, AEC-DOS j
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F. U cs t e rn, AL'C -IISS' OT11EES_
A. Court, B:'l F. P. Co.:an, B::L K. Do..nen, E: L J. B. !!.1:uper, E :L D. Tuleston, B:'l C. J. Race.an, B.L N
D. Schueller, AEC-PA0
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Mt. Downes opened the ecct i n'; by recapitulat in< the histor / : ~ --a revis ion project.
E';L has been asked to ansucr the question as :: -a
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raximum da: rage t hat could result fron a reactor accident.
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ucre to obtai n prel ic ina ry renuit e. by Octobcr 1 and a final draf t Octobc: 31.
Tne t it!c propo: ed by.'.:L uoald bc "Linits or Li ab i l' -
l Patentiai at-tne nccleental
.,c.: car - c :.
- s = : cn :'roduc ts t rom a a_. :.
i I;u ! car Pcuer Plant."
A.s i n 'J H-7!.0 the followi ng criteria uere : : ;
1 applied at every sta ;c of the s tucy:
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1.
Given the choice of assumptions, take the tc.ost pessinistic of the ones that cannot be shown l
f alse; and 2.
Liability is the sum of' the loss of physical l
assets,. rcal and potent ial, sustained as a result of a fission prode t release.
Mr. Da* ncs a:>ked the Steering Cccittec whether these criteria veri 2 propriate, keeping in mind that stricc application of these criteria 1 cads t: " sry horrib le 5 they were results.
Messrs. Staebler and I'. Ccol expressed their vicu that si-:
1 caving cut statistics, the sare res ult uculd be reached as in '4AE2..
O and, if so, there was no point to the study.
Mr Dc.mes agreed that airc:: :entical
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results were obtai ned as in '.-? ASH-740, the only dif f erence being t}E.ctension to hi r,hc r pcuer le tel s.
Messrs. Sty.'nle nnd 4Cnn1 numtioned Mr.Dounes about the cr::"-11 plan Mr. Dounas sa id - :. E:L did to plot probabilities of accidents versus ccsts.
believe they had anything to contribute en the rattcr of the - : :.bility not of an accident ar.d that thir. part as Icf: for AEC to handle. Mc i:fd that 3::L uns consid' ring was for random f actors c::t-relcast the probability that e
(e.g., re tcorolo;;y).
Dr. '.:insche stated that B::L did no t sca hc. 5
'.1 accident prcbabilities could be exten3cd to the probahility of a larre ac:!: -t, Tacir vieu uns that those stat ist icians propcsin~, such a schere right it :- sidered frin;e members of the statistical co munity. Dr.Dann stated that
-hout considerations of probability the ef f ect of the report would be t: ' 2".p cxtend Price-Anderson ir.dcnnity, but, at the sate time, to strer;;..a-the basis of those uho oppose mre nuclear pcuer.
Dr. Bech added that there should be anc ether criterion, nar:.
In takin,, the co rse si tua t ion, one shculd acccunt fo: the se ;uence cf ents uhich my ic;31j the unlikeliner of the event and give pern7ceti": - the size of the acciden'..
He askcd i f I'::L i nt er. icd to de so, at leas; qualitatively.
In response to th is ':r. Dennes s uggest ed lookin; a.
-he second stage of their project which he had cutli-cd on the board ;3 f: 11c.:s :
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- Choice Parc eters 103 n?e 2,500 ".;th j
Peucr l
2 years Cjele tir2 1.0 Fraction of core elt l
Fraction leaving core:
1.0 Iodincs 1
1.0 Use 55 I;obic gancs i
t ps 007 or.50
'lara Ca r th, ':b, Zr 005 or.50 Usc 4-day dese Sr, Ba based on ::CRP Cs, Mo, nu, RS, Te, Tc 1.0 Tables i
2 O or.80 (1/2 m hole; !.S hr.)
Fract ion of above ret:'i n2d in contoi: Tent
.cl.
Meteorology
!;i ght (In>crsion).50 er.75 of ti:ce Day (Lapsc).50 or.25 1;o inversion in city Upper lid to diffusien Light rain Deposi t ion cha ra ctcr int i c of 0. 5 T.i crc par ti c les
'Jind va riat ion :ith hei;;ht Damage Icycis:
Peopic:
nid -lethn ! 12CO r to G1 tract 2
Land:
Iodine: FRC gives 2 x 10 6 c,r 1.
Population Dietribution: Prenent: P (i.n circle of radius R) =
2 2C0 L2.53 to 20 miles; ther 6CC penn. ic / :.i
--R,/36./-
600.
2.
Urban pop. dens. = 7?.00 cy.p /
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. Mr. Daunes stared that they wrc able to find no basic for clininating 1007. cere cit.
S tar bic; aded if there had been any calculat ions,
nl:ce cxperien:e dcen not support ICCZ.
Dr. Ecch added that he hac asked for such,n ect: nie for LCFI and there hw not yet been a loss of coolant Dr. '.:insche indinc red that the after-heat accident fc a lar e react.r.
van sufficient to predute the raltin3 iic said that a factor of 9 uas he a chan;e by at least a factor of 10 uniuport nt, ar ' ti- '. th er e m.; t to.r.ahe any rcal dif f erenec in the results.
Mr. Dounec ntated that the relcane fractions uere based on Miss Court's study..hich indicatcc that they depend strongly on chethcr or nct oxidus are f erred, since some of these are very volatilc uhile
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others tend to remain in L1 r
- relt, la renponse to a question from Dr. Doan, I'r. Dounes said that there were differences at this stage compared to WASH-740, but not in tim final result.
Fcr enarpic, with regard to st rontium the pouer cyc!c had been increcned by a f actor of the f raction of ctrontium leaving the core hcd been decreased by a 2 and dif f orcnce uas in the fraction retaincd in the factor of 2.
Tn e i.portant te. McCool sched if fuel element mterial uas important.
Mr. Downes shell.
there cas no apparent dif f erence hetucen oxides and ccrbides and said that that nothing ccn keep volatile onides in a het core, imL has Icohed at a niny experirental reports and thcy.:crce all ~. ore or lecs identical l
great in this regard.
Mr. Dcunca statcd that if contain ent uorks, there is 100% retentien.
if a hole in the containment results, the rw.imum accurt that could
- Houaver, be rele, sed could de.cni en the niac of the hole, cnd s ince there ves no casis o
for a choice thtj hac arbitrarily choren 1/^ c.
Tacj had asked thcmselves uhtther an appreciabic f ractica could get 1ctt on the way out, but fcund no basis for concluding thin.
Mr. Ocunes scid that they bcsed their land contanination values for icdine on the FRC PAC rcport (Peport I:o. 5).
Ihc propoced futurc F2C report f or Cn, etc. ce=ot be f actcred in.ncu.
'1 hey 100 km the levcis ucre still 100 tires the FAG.
Tac result if found that at a city were involved uculd be catastrophic and there would be deathc cut to if 0 1.m.
In responce to a question f ron Dr. Doan, :*r. Downes stated that it vould tal:c cne hour to relt SCT. o f th e c ore and one day for 100 7..
He not ed that MA511-740 uculd give almost cxactlj the same results using the higher power icvel:>.
Dr. Doan anhed hc.: :.equentij the retccrciogical assu ntions would cbtain.
Mr. Smith replied that for exarple in the regica bet. aen 2::L and tic that thene conditions cecur CO days a year. !!c statcd that rest studies h ve accur.cd a deep rcdiction invercien over a city, bu ; that it has been Econd Instcad a ucak lapse c:.:ists up that such invcrsion alrast never occur 3 to 300 m, uith a cappin; invercien above.
i'nder thenc conditions, heucv2r,
more people would be exposed, as a result of tuo factors: 1. Tac avers;c tind
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speed increases with height and thus cuts doun on travel time; and 2. Tncre is an upper lid to diffusion rahing it a lit:1c ucrse at larac dintanacs.
nothin; in the =cteorology could change the end results
!!r. Smith f elt that by core than a f actor of 2 or 3.
!!r Dounes stated that since even a sophisticated approach such as this had produceri no significant di f f erences fror W.5L740, BSL vishec at this time to obtain f urther c,uidance f rom Lt.c co=ittec.'
Mr. licCool statcd that c
this was the result of the basic assur, tion: If it cannot ba prov aron;,
than the end results follcu. lie noted that there was no tantion of probabilitics.
Dr. Winsche replied that tuo prcbabilitics can be considered:
1.
The probability of havir ; an~ accident at all and then the other assurptions follouing; and 2.
Tne prchability of an accident causing rupture of contai ment and again the other assumpticns f ollow.
Ane engineered safeguards could:
1.
Limit the probability of loss of coolant accidents; and 2.
Limit the Dr. Uinsche stated that there probabilities probability of contain=:nt rupture.
could be cultiplied.
lir. I!cCcc1 f elt that this narrcued dcun tc tuo anal /ses:
it either uccks or it does not; everything else falls betueen there.
Mr. Dernes stated that, for exa=ple, randerncss if totcorology would c.ake no dif f erence; a catastrophe still results.
Dr. Claus then statcd that ha uas con:cr.ned about the direc; ion this
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report was taking.
It appeared to hir to be a -ixture of arbitrary (albeit s
cha ra ct e r is t i cs,
possibly crpert) choice of a feu 'inda cf accident calculation of the phys ical con '1uer.ces of aud. caituril/ chcr:n sc:idertr,
and attempts to assess the costs of suth accidents despite lit:1c if any b: sis for attaching rency value to a holocaust. lic felt that what uns necdus, aside frcm probability, vere cal: ulaticas for a brcadcr spectru, of various hirds of These cculd then be celatcd to their probabilitics cnd liabili:.y accidcnts.
dollar estir.:t es' en it.
Instead of being con:crned abrut experts could put release rechanisra, use a series of assumed releases and then go back and f actor in probability.
Mr. Douncs replied that this cculd be done uith regard to fractions of core ec1t but not uith regard to the relence fractions.
they h d aircady done and f urtherr.cre Dr. Kuper stated that that was t.a t Dr. Winsche they ucre not responsible for the question of probability.
suggested that it might be ross ibic to use the several groups of cicrents 1 caving the core (see Tabic, page 2) as the basis for the preposed spectrum of conditions.
!ir. S taebler asked rhethcr sort iodine uculd not he stopped before tcrperatures under 3C00, tir. Deunas gett ing out since it d e pe r, i t s at replied that in their opinion the t ire would be teo short for apprctisble deposition: f ur.hcrrore, they assured that the interior of the centainment is painte<!.
Thcre :as no dif f icult:. in -ahin; a series of release assu~tiens.
The end recuit uculd be prepcrtional to ccre relt.
P.r. Stacbler felt t h '.
there was a better nurber f or the arount of relcase: there was ne prcof that it will rot get out, but all the cvidence so far is that it aill net.
Dr. Winsche said that the irportant f actor here was the surface to volu=2 ratio and not the arount of heat generat cd.
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. I starting uith the BML Scch then preposed a dif f erent approach:
Dr.
irotopes, calculat e cortality, etc.
assumptions, take the 5 groups of and obtain the accident that and then co bach to the thoice of accident Mr. Dawnes c.oted that the do:c to the GI pertains to a given perccata",c.
cxtern,1 dose was not significant.
limiting factor and that rasks or shelter -che little di f f erence in the results and tract uns thg I'r. McCool f el t that He stated that 3 groups of isotopes are cent ro11ing. term with no method to describe the that at Icast this uas mercl/ regulatin;; the scur:0 if BNL really believed a large Mr. Downes replied that release techanism.
it could be donc but still it f raction of any one group would be retained, would not significantly change the result.
th a t t$ey had accounted for Dr. Vinsche stated that Brochhaven f elt including particle size ef f ects.
They did not depos ition mechanisms,particic agg1cmcration to occur since higher concentrations expect significant real conditions are likely to give core would be needed.
Tncy did adcit that aggiorcraticn than laboratory conditions but since the density of such transpart would be pretty loose struc ture, oggicaerates are lov due to their much the same.
Dr. Winsche asked for the Cortcittee's opinion on waiting until the Dr. Beck replied that in his opinion FEC produces PAC's for strontium, etc.
such guidance would be negligibic.
Dr. Kuper said that their tne effect ef fect since they could not disagree f eelint va2 that there would be a great icvel of with FRC nurbars and thus these numbers would detcraine at what contaminatien one uculd pay for land.
Dr. Cowan said that he had. talked with Mr. Palmiter of the FRC and that ~here was sc=e hope of getting the They were having dif ficulty with the matter of PAG report out in January.
exposure being sprecd out over many years. BNL felt that perhaps they should unit until their thinking uas crystaliced.
the result would be if the contain=cnt worked.
Mr. McCool asked what Mr. Downcs replied that ' the damage vould be stall (on the order of $1,CCO,CCO).
Dr. Doan asked about credit for safeguards. He f elt that this ceuld not be Dr. Vinsche said that bringin;, in the ratter of probability.
donc without if a given consideration of safeguards might be helpf ul in the sense that safeguard took the darages out of the catastrophic range, one could dif ferentiate anang safeguards as to which might be most profitably stud ied in the future.
Dr. Beck stated that there would pmbably bc very little dif ference between saf eguards.
f or the 5 nuclide groups, each in turn eculd Dr. Beck suggested that varied to give a paraectric study, and then one be held constant and the rest Tae reqeired to give a certain result.
could detcimine the type of accident could give /. or 5 cxarple ; of accicents and the reader could interpolate among these.
Dr. '.h nsche sa id that given the ir assumption of core telt they re po rt Dr. Beck fcit that would have to choose the rc:uinin", assumptions as uell.
a Icu conditions could 'be assumed such as ef fec tive containr nt, different s.m,
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- i vi r-the results for 1007 521' "ith a bir nale ana riate in a 7,iven case o
gg ppro icak rate, g1-.,. to do this would 1
The burden of prcor as to U"i rsche replicc, g
each.
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vauld be left to cach group.
ch-assumpt ionr, uould have to be changc-proposed. He f elt they coul-but the i t not be diff.icult, 1.
r_ par, ri,.i.
1 2.s e hnt,s change thcir mind and it,: auld not be thc sre:
c take anc ther Icoh at the deposition probic.
his was appropriate release f ract ion 5-
- o vait until their cun thinking about
'.r. Douncs said that they
,an,-
He felt that they ucrc likaly.
was clear before asking for othcr peop cos.r of f ered to give E;;L tha s
s +' e cu c's t io ns.
r.ov recdy to ask the ri cht names of 5000 CPPIUP#iU " E p1c' dif iculty has been highlighted: nacaly,
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Dr. Doan stated that involved.
'With reg:rd to o
we cannot shou the spc:trum o-pre o li iecctastrophe even though uc do not c
- 1er stated that there uere a great limits of liability we canno ru 5ta believe it will ever happen.
nevertheless cannot be considered rany things that ecnnot be rule o'a t but ughts on the shape of the, Do es s
ac crcqPale eVC(({
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dreu the f ollowing curve for the probability d
to the outsi.e.
probabili ty dis-.. u -a given fraction inside the contain,_.,n' r"u'd get that 1
1 Darage l
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10 100
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If it looked like the fo11 cuing, then there would be some worthwhile basis for considering probability:
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7-Dr. Beck stated that he had in mind a similar curve as follows:
Safeguards make Damage littic difference 10 " "I
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1007.
Preb.
Dr. Winsche said that some f actors may be subject to change threugh" design of the rcactor but that BSL f c1t that they sfould not be.
Dr. Beck said he was convinced this upper limit accident must appear in the report but there I
wasstill a need to factor in sms11cr accidents.
In reply to a question f rom Dr. Beck, Mr. Downcs said that cycle time had littic ef f ect on the results.
Dr. Dean felt that this was an important conclusion.
In reply to a quest ion f rc,e Dr. Okrent, Mr. Downes noted that the effect of iodinc on peopic was negligibic ne::t to cr.posures f rom the GI tract.
Dr. Cowan said that in the lethal range, the contribution of sodine
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could be ignored. In a range where injury is involved, it might rake a difference. lic stated that the external deses f rom the nobic gases would amount to about 50 r as compared to 1200 r internally to the GI tract, tir. Smith noted that the nobic gases ucre negligibic only f or the tpper limit accident and that for smaller accidents they may not be so negligibic.
'ihere was f urther discussion on the relative contributicas of external and internal exposures f rom the dif f erent isotope groups.
Tne CNL representr.t ives I
j in general felt that the relat ive contributions would not be very dif f erent I
for the smalle-accidents.
Dr. Kuper noted that these were artificial asse npt ions and they vauld not materially change the end results.
Dr. Winsche stacco that they would thinh f urther about the dep 3si ticn qu2st ion, lie noted that it has been studied exten:ively outside the nucicar field and he was not convinced it had been Icohed at sufficiently.
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Dr. Beck asked if th'c computer programs were ready.
Mr. Dounes 4
replicd that they acre runnitc, bu. the results were fright ening.
Dr. Uinsche
, no ted that ' unicss some mach..nist can be found to make their assunptions the nur' crs Ioch pret.t y bad.
Dr. Ecek inquired about the loss t
inpossibic, sce.cd ridiculcus assumptions.
!ir. Douncs indicated that at these IcVels it a
to refine then.
Dr. Claus inqu red what they intenled to do uith rcg:rd to the injury category.
Dr. Kuper said it uas actus11y a question that could be Dr. Ccwan indicated that uith regard to the non-1cthal dealt with later.
category they uculd use the latest (T.: nucher of 1 or 2 per 5.illion per rad I
per year to get the nun:ber of can:crs produced.
'Ihis vill be a large nurber and may be comparabic to the acute results.
- Ir Dcwnes noted that evacer. tion had been considered but was considered icpractical to include.
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CLUEP.AL SESS10M - 2:15 p.m.
- 3:15 p.m.
f it.
Dr. Beck outlined to the BUL peopic the report as he envisioned The first section uculdJeal ;i th Probabili ty.
He noted that tuo groups are this section could be written to ref1te studying this question and thatThe se:ond sectic:' would deal with f actors having an expericace to date.
of accidentr., such as release fractions,
ir. po r t ant effcet on the concequ;necs include a pararctric study of the 5 groups of fractions contained; it uould The third section would nuclides f or which the result s could be tabulated.
cocprise exampics of various degrees of accidents including a contained accident, accident.
I' t.m nd sc=c distance the calcula tional method breaks doun, thus the calculat ions becore meaningless or unbelievabic.
f Mr. Downco noted that 3:!L would pick an appropriate After some diccussion it was decided that limit as to the distance beyond u'aich f urther calculation vould not be Mr. McCool noted that we still did not have an esticate of an upper cut-off licit for the dollar liability.
Dr. Beck said that if the reasonabi c.
of N dollars, it could be stated
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h,f first three cases have an upper limit Mr. Dcunes indicated that they the fourth case is far beyond that.
He noted that
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that would pich a value beyond wh.c. they. culd not calcula te.
the outline was acccptabic bet that it could tche sore tira to produce y
the indica *.cd results.
Dr. Beck asked about their intcations uith regard to isotopes forenke Dr. Couan stated it uould probably not which FRC has r,1ven no FAG's.
much dif f erence once icdinc in rilk and st rontium and cesiur on land ar DJL could go ahead based on a preliminary fec1 with accounted for. lic felt There uns some discussion on hcu soon regard to FRC's probabic findings.
and it was decided that SSL the FRC was likely to get out the neu EAG report would go ahcad using their best judgr nt and that if dif ficuitics arose, Mr. Downcs indicated that they nodifications could be made accordingly.
to have results tabulated by mid-Novembm-with the first draf t scrc-cypect tir.;c in Deccrber.
that the ACC had had c.any of fers of assistance but Dr. Beck noted that There has been sere discu;rien uith AIF and the AEC these had been parried.
to their saf ety committcc for comment.
uould like to subrit the first draftto be done bcfore they completa their final Mc. Downes said he uculd like thir first draf t of the report.
Lr. Beck felt that ue should subrit the repert to their princi pal int erest would be in them in draft f o mn.
Dr. Lc n noted that interested in the matter of various the first section since that cor:-it t cc w.v safeguards.
Mr. Stacbicr sug;csted that pcrhaps the Stccring Cerrittee shculd talk with this AIF Craup.
Dr. Doan felt it uculd be interesting to find out h
what an independent group uculd suggest for a report on this s ub j e c t. ile felti n
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it would be ruch mre dif ficuexi s t s ; nar.aly, that it was difficult to do withcut lt resolve the dilc-a that the same tire it uns difficult to prove that
- build, fer. Beck noted that it appeared there.:as Price Anderson inder.ity and at AIF ideas particular]j are sa f e eno.::. t o reactorn agrecrant and that it might bc worth;iile to get on the quest ica of probacili tj.
Mr. Dc.:nct Dr. Beck asked if E::L intended to talk with other groups.
Dr. Bcck j
questions.
the;.:cre nou readj to ask the right the report ray surprisc that he felt the =ceting had Secn prcfitabic, th:t ill be more useful i nd ! r at <..
sore pecole, but on the basis of the agreed outline it w st e.r c than he had hoped it would be.
recting, Mr. Douncs said that when With regard to a time f or the next nailcble, he will ge; in touth curves or tabics of the early results are d make a choice at with Dr. Ecck probably scretica around early November an time as to an appropriate date.
that T ROOM ALC PUBLr' COCU'. r"
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