ML19320B788

Radiation Exposure Due to Venting TMI-2 Reactor Bldg Atmosphere

ML19320B788
Person / Time
Site:	Crane
Issue date:	06/12/1980
From:	Franke B, Teufel D INSTITUTE FOR ENERGY & ENVIRONMENTAL RESEARCH, HEIDEL
To:
References
NUDOCS 8007150042
Download: ML19320B788 (23)

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{{#Wiki_filter:}. / 0 1. 1 I RADIAT10N'EXDOSURE SUE TO VENTING TMI-2 REACTOR $UILDING ATMOSPHERE ~ I A Study Prepared by the" Institute for Energy and Environmental Research, Heidelberg',I Federal Republic 4 of, Germany for the Three Mile Island Legal Fund, We hingt'en, D.C. Bernd Franke and Dieter Teufel 4 Heidelberg, June 12, 1980 {

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.m i Table of Centents Sursary........................................ 1 3* 1, Introduction...................................

2. Radiological Ir. pact of Cther Radienuclides 3

Excluding Krypton-85.......................... 2.1. General Situation........................... 3 6 2.2. Potential Radiation Exposures............... 6

3. Rat, iological I:: pacts by Krypton Venting........ 8 3.1. Individual Doses...........................

8 3.2. Collective Doses.......................... 11 3.3. Potential Health Effects......... 12

4. Sensitivity of Radiological Environmental 14 Program......................................

Acknowledgements............................... 18 i 19 References...................................... 9 6 I lf i 1 I t -.-=..:...-* * * " ' ' ' ' ' " * ' ...., _ _, =,, = - - 'l '**'.'_.l. **'.,. '.:*.:... ~. j{.7_. .:~9*"* e ,,,,,,,L.i'.1. 2; r., - j. : ". * " * * * * " ' _ _ ' * * * * '~p l -a?. :T-*: 3-*_ ::b: ;;'^ -+ ^ ..:.7 ..' ::- 4:;.:y.-...;;a :__ '.5: - :3._.. .._ Q;.~,gi :._;Q;. .. z _ _ __ ::._. 3[.--3=_ .- :=. - :-.:.=. ; g.= .. = :- g -gEj..,. ; : 8 ..;a _. j 1 g.: i.-t _. g:q ,7..r.;....;-- .j = - -. ~. + .:;... _.. __:;.3_ j = ~== i' ~ - ~ ' .z- -- '~ = e 4 I

l su--ary This study analyses the radiological assessments made by the l Metropolitan Idison Company and the U.S. Nuclear Regulatory Cceraission for the proposed ventj ng of the atmosphere within the TMI-2 reactor building. dur findings are: I i

1. Previous discussion of the venting of radicactive gases l

from TMI-2 has concerned only the_ noble gas krypton-85. t Besides krypten-85, the afmosphere of the reacter buil-ding includes a great number of other radionuclides, some of which would be released into the.tnvironment durin,g the blev off of the gases. This could lead to radiation exposures significantly higher than those cau-sed by krypton-85. The most important radionuclides, which have not been sufficiently considered so far include: C 14, Co 60, Sr 89, Sr 90, Ru 106, Cs 134, Cs 137, Pu 239, Pu 241 and others. Ivcn allowing for high filter effi-ciency, a model calculation for only three of these nu-clides showed that population doses would be high enough to cause about three additional cancer cases and an equi-valent amount of genetical damage.

2. Uncertainties inherent in the meteorological models and dose calculations mean that it is impossible to exclude that in the proposed pu:ge program individual skin doses due to krypten-85 ceuld exceed the 10 mrem limit.

3. Istimates of health damage should consider not only re-gicnal but also glebal pcpulation deses which are an in-dication of all health effects caused by the release of 1

radioactivity. Both can be estimated only with great un-certainty. The dese effect relation is subject to wide 4 4 ,-- -.=;r-y- + _.2 m.n --._:... _ j;,,,, ~ .+. ~1h :. .__;--- '~ ~ * " L' ?l L&;^B= -- \\ :.-. ~ ' = ~ "-:."& =L - ~ . -e: -- --+:

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g-i 4 1 i scientific discussion. We cannot exclude that venting l krypton-85 alone could cause at least one additional cancer case (probably skin cancer) plus one case of ge-netic damage within the next century. However nothing is known about a potential synergism between krypton-85 beta and, ultraviolet radiation. 4 The environmental monitoring program cannot ensure that all significant radiation doses to the community as a l result of decentamination of the atmosphere of the TMI-2 reactor building atmosphere will'be detected. Mest mea-surements are not frequent enough and are not made at all in some 1:::portant localities. Impcrtant pathways and radionuclides are neglected.

5. As censiderable health damage could be caused by venting the atmosphere of the TMI-2 reacter building, we strong-ly advise against this procedure. The report of the Union of Concerned Scientists concludes that decentamination is not as urgent as stated by Met Ed and NRC. Therefore, we strongly recc= mend that the alternative methods for decentamination proposed by UCS and Prof. Morgan be used.

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1. Introduction On April 23, 1980, the Institute for Energy and Environmen-tal Research.was' asked by the Three Miles Island Legal Fund to prepare a study on the community radiation exposure that could be expected if the atmosphere of the TMI-2 reactor ~

was vented. We did not receive deta'11ed information en the plans of Met Ed and NRC's statements un'til May 23, and therefore had only limited time to prepara this report. For this reason we can give~only preliminary results and pose questions which shei215. be analyzed in more detail. How-aver, we believe that our study'may indicate some aspects of the proposed venting which have not been censidered by Met Ed, NRC, and UCS.

2. Radiological Imoact of other radionuclides excluding krypton-85 2.1. General situation Table 1 summarizes the result of the computer run with an CRIGEN program for the present'radionuclide inventory at TMI-2. Only nuclide's with more than one curie are listed.

In their radicecological assessment, Met Ed, NRC, and UCS considered enly one of these 71 nuclides to be relevant - krypton-85. However, because of different volatilities, only a small part of the inventory of most nuclides would be present in tihe containment atmosphere. Measurements of the centainment inventory have been made only by the Met Ed. No independent control measurement was made. Furthermore, in their 1979 re-report Met Ed caly listed measurements of 13 nuclides (i.e. I Co 58, Co 60, X: 85, Xe 1:1m, Xe 133m, Xe 133, Xe 135, Cs 134, 3.. gg._;.g. _ _ ;;gg=3.; g =.y .g______ y

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• ="la is Radionuclide Inventory of*TMI-2 at July 31, 1980 (activity > 1 C1)

Nuclide Half-1.ife Inventory (C1) Nuclide Hal f-1.if e Inventory (C1) H 3 12.3 a 3 800. T* 127m 109. d 11 000. Mn 54 312. d 25 000.. Te 129 1.2 h 62. Fe 55 2.7 a 29 000. Te 129m 34.1 d 96. to 58 70.8 d 26 000. Cs 134 2.1 a 220 000. 6 Fe 59

45. d 4 300.

Cs 135 2 10 3 4,3 Ni 59 75 000. a 70. Cs13}

30. a 8SO 000.

Co 60 5.3 a 300 000. 2a 137m 2.6 m 830 000. Ni 63 100. a 10 000 Ce 141 32.5 d 3 600. Se 79 65 000. a 3.3 Ce 144 284 d 7 700 000. Kr 85 10.8 a 95 000. Pr 144 17.3 m 7 700 000. Sr 89 50.5 d 90 000. Pr 144m 7.2 m 92 000. Sr 90 28.1 a 790 000. Pm 147 2.5 a 2 300 000. Y 90 2.8 d 790 000. Pm 148 5.4 d 19. . Y 91 58.8 d 260 000. Pm 148m - 41.3 d 340. 6 2r 93 1.5 10 a 17. Sm 151

87. a 6 700.

Ab 93m ~13.6 a 1.2 Eu 152 12.4 a 35, Nb 95

35. d 1 000 000.

Gd 153 242. d 19. Nb 95m 3.8 d 3 400. Eu 154

16. a 12 000.

2r 35 65.5 d 460 00J. Eu 155 1.8 a 20 000. Tc 99 210 000. a 120. Tb 160 72.1 d 11. Ru 103 39.5 d 13 000. Th 231 25.6 h 3.3 Rh 103m

57. m 11 000.

Pa 233

27. d 1.

'.300 000. Th 234 24.1 d 18. Rh 106

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Ru 106 1. a 1 300 000. U 235 7 10 a 3.3 7 Ag 110

25. s 14 lU 236 2.3 10 a 4.1 49 110m 250. d 1 000.

Np 237 2.1 106, j, Cd 113m 13.6 a 110. U 237 6.8 d 2.3 I Cd 115m 43. d 12. Fu 238 87.8 d 1 000. 9 Sn 119m 245. d 290. U 238 4.5 10 a 18. Sn 123 129. d 3 300. Fu 239 24 390. a 7 900. Sb 124 60.3 d 10. Pu 240 6 537. a 2 200. 5b 125 2.7 a 42 000. Am 241 433. a 220. Te 125m

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.... i i t Cs 136, Cs.137, Ba 140 and La,140). In the 1980 report (Met Ed, -1980) additional values for gross beta activity are given. A rough extrapolation'is made for I 129. In addition, NRC gives a value for tritium concentration. Also, some measurements of strontium-89/90 activities exist. 63 of the '71 nuclides in table 1 are neglected by Met'Ed and NRC, although they focused attentien on other nuclides (e.g. I 131, Xe 133 and others) with such a icw activity as to be indeed irrelevant. Met Ed's measurements of radionuclide contentration in the-l reactor atmosphere vary by up to seven orders of magnitude. According to table 2-1 in (Met Ed, 1979), within 5 days (frcm June 21, 1979 to June 26, 1979) air concentrations , of cobalt 60 increased by a f acter of ~46 000 000 and of cesium 137 increased by a f actor ef a 1 500 000. The last reported measurements of september 26, 1979 showed smaller values than those frem J,une 26, 1979. but as can be seen from the data of gross beta analysis (Met Ed, 1980) during the month of November and December, a censiderable rise of airborne concentrations was reported. Either the at-mospheric cencentrations are constantly changing or the re-sults_are not reproducable for other reasons. In any event the worst possible case should be considered. We have doubts that the "best estimate" provided by Met Ed describes the actual state and can be relied on as representing conditions during' venting. There is a risk that during the venting par-ticulates from the walls and flecrs could volatilize and thus lead to a rise in reactor air. concentrations. If, for example, maxi =um values for airborne activity as shown in table 2-1 (Met Ed, 1979) existed during venting, the total inventory of airbcrne Cs 137 and Co 60 could be about 790 Ci and 45 C1 respectively. Even with the assumed filter efficiency of 99 % (instead of Met Ed's 90 % estimate) l 7.9 Ci of Cs 137 and 0.45 Ci of Co 60 would be released. 4 e ~

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. -.. - ?otential radiation exposures of radienuclides excluding krypton-85 are discussed in section 2.2. We conclude here that it is essential to measuhe the amount of each radio-nuclide present in the reactcu atmosphere and to estimate-the potential release rate during venting,the range of as-sociated uncertainty. 2.2. Potential radiation'execsures The relevance of the above considerations is clear'frem our estimate of the potential health effects of a release of selected radienuclides. We' present cur results in ta,ble 2. Individual radiation doses (50 year commitment) were calcu-lated for three nuclides ( Cs 134, Cs 137, and Co 60), as- -6 8 suming moderate atmospheric' dispersion (1' = 1 x 10 sec/m ) -2 and a deposition velocity 'of 1.3 x.10 m/sec. We assumed that persons would take only half of their food frem the area i of maximum concentration. Calculatiens were made according to default values in the German Federal Regulation Guide (BMI, 1979) except the dose conversien facters which are ta ' ken frcm BRULAND et al.,(1978 and 1979). -Radiati,cn exposures frem cther radienuclides and by other exposure pathways (such as inhalatien, ground exposure etc.) were not censidered. The calculated ingestion dose to whole body.cf 530 mrem and to kidney of 7 500 mrem is considerab-ly higher than NRC's limits for public radiation expesures. In cur consideratiens of all health effects, we estimated population deses which wculd be of the crder of 2 800 man-rem, about 30. times the whole body populatica dose by kryp-ten-85. Assuming the incidence of ene cancer case per 1 000 (SOKMITZ-TIUERHAKE et al.,1979), three additional man-rem cancer cases could re'sult frem the release of the three ra-dienuclides censidere'd. In addition, an equivalent amount } cf genetic da= age is estimated. I A further problem is represented by the radienuclide car-l j I bon-14, presumsbly present in TMI-2 to the order of a few j ' curies in gas form. Because of its very long half-life t -WOLI'IE?d;- =r_ _ _ __ E Z.-- : 2... _ T;_:= _ _ _ 7 - _. _. _.. _ _ _. _., ~ E =t r _ _.....,_._a c._. i=, = m=Z. _ _ _ _ mumm =m wzm== = _m_- ,,R g i P i i b

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dii;I;ill. u 'Q 41j!! l lhh (lijf i !!!O !!I;i $ ; jYI,' idis! Table 2: Potential Itadiation Exposure by I:adionuclidea other than krypton-85 th I E'# i$ i llelease / b DoseCommittment(mrem)lCollectiveDos SO Year Individual hff!!' Total Inventory Maximum Inventory to Whole flody ""CIId" U * " ptcr Ate.os-Id plI! at July 31, 1980 in Itea i "#"~"" whole body critical organ I

l d b..

j; Co 60 300 000 C1 45 Ci 0.45 Ci 0 34 8 160 (liver)l e di 3 u. 420 h! 1 40hidney/1 Cs 134 220 000 C1 200 C1 2. C1 130 ( i I m w fih'l:lnl! I Cs 137 880 000 Ci 790 C1 7.9 C1 390 6 100 8 .2 200 j (kidneyJl ]!]j .b... l 2 800 y Total 530 yp! e Ue!! .I

it.\\"}#

if W J!:i! 1979); maximum values for Co 60 and Cs 237; concentration for Cs 134 cossected, 7; :!f. al calculated from table 2-1 in (rfet Ed,

[

as Het Ed values are inconsistent [i .i.hii fit;!' b) filter efficiency of 991 assumed L c) see text ~ le.g. sector ens at rnt) c tstimated from UNSCCAR (1977) assuming a region with population ocasily of 200 km j dp correction factor of 2 for varying of radioccological pasameters _ from the mean value of UNSCCAR y u@a ! !.in

-S-1 (5 730 years), it will ' cause considerable population doses although individual. doses in the vicinity of the belease will be small.'Cne C1 of carbon-14 would lead to population doses of 400 to 590 man-rem, when integrated over the whole decay period (KILLOUGH and RCHWER, 1978). Compared with the whole body'pepulation dose due to krypton-85, release of only one Ci of carbon-14 would lead to doses and he'nce to health effects.five times greater. The radionuclides con-sidered by us to be most relevant for individual and col-lective doses inc3ude C 14,'Co 60,,Sr 89, Sr 90, Ru 106, Cs'134, Cs 137, Pu'239, Pu 241 and others. Detailed-investi-gations are necessary.

3. Radiological impacts bv krypton venting.

Met Id is planning to release about 57 000 curies of radio-active krypten-85 into the atmosphere to decentaminate TMI-2 reactor building. Met Ed proposes to vent and flush the re-actor building through a 160-foot vent pipe ever a period of five to 50 days. 3.1. Individual doses To stay within MRC's regulatory limits of to CFR 50, Appendix I, noble gas skin doses should not exceed 15 mrem. Since k 'NRC anticipates additional radiation exposures in t.e course of this year they propose a limit of 10 mrem. We agree with Met Ed and NT,0 that the skin dese due to kryp-ton-SS is the most relevant dose.contributien to the indivi-dual. Me.t Ed plans to release radioactivity from the plant stack under favourable meteorological donditions. Since these cen-ditions are calculated by a cceputer, att'ention must be j payed to the input data, i The calculated radiatien.dese depends linearely en the re-i teorological dispersion factor used. Met Ed did not indicat'e the source of their data frem which S hk kr -IY:.EE EE=: ~9.=.T.5r_5 ! ="f. f _ __.-'4Eifi. g.g.:: -Hika:f.5TfdfM-558 =.l_bTl@_d3 -- g-- .g..= =..;__._.gg.g.g._gg - = _ - = -,. .... - --- --- = j I i ~ 1 e 9 b

- the meteorological dis'persion,f actor X is computed in de-f pendence of stability. classes, wind speed and release height. i : However, it is clear that the data set used by Met Ed is shows the variation of not the only cne available. Figure 1 meteorological dispersion as a function of the distance for a special weather situation and for certain distance fr'om the emission source. When c;cparing the data sets from five different authors, we find a factor higher than 100 for )f. 000 m downwind. For other meteorological situations, 1 at a smaller variation is found. Since each data set presents mean values originally derived fron.several measurements, there is an additional uncertainty of up to one order of magnitude. Therefore, the question of data sets is in fact highly relevant to whether or not Met Ed cnly releases under f avourable weather conditions. We foun'd 'that under all weather cond'itions Met Ed calculations may underestimate actual doses up to more than one order of magnitude. The meteorological program proposei by Met Ed should ensure that environmental doses do not ex:eed the 10 mrem-limit , however, take the uncertainties des-skin dose. They do not cribed into account. Secondly, variatiens in dose f actor calculations are ignored by NRC and Het Id. The skin dose i=mersion factor is given ~1). by NRC and, Met Ed as 4.3 x 10" (rem x m' x Ci" x sec NCRP report no. 44 (NCRP,1975) gives a sumary of dose f e-tor. calculations by different authors. The results depend I 'en the. assumed skin layer thickness. The report's estimate ~I ~l), about -2 8 is a value of 5.7 x 10 (rem x m x Ci x sec one third hignet than NRC's value. but Whole body dose factors also vary by more than 100 %, since the gamma radiation of krypton-85 is low, whole body dose is less important than skin dese. Ccmpared to the uncertainty due to the metecrological cal-m=,:. n

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!g i N s/m ! l' i l ~5 Release Ilcight: 75 m 2xio - 1 p 'k Stability Class: F -i Wind Speed: 1 m/sec (l lj gxio - s&~ n ~~ -6; q. i, 8x10 Mrtin/Tickvai t 0 f) 6 . l? 6x10~ ~ h-J & g - ~. Q j b9 pp g-i ~ ~ u y, _ _g;;,_F -6_ 4x10 A Y 2 'O' ---o Ceiss --x I:!! / / p- -- -o. lyj s ~ ~D y - M I j'j t in l 2x10 ~ u / ~6 / ,[' / (( ik / lh ni -6 x usea in usu-ss. a j! H E 1"' ~ 8xto"#- / [ ti!i!l} l 6x10' [ 4x10' - I !'i! / ld :![: 1 r 7 i. ".x10 I !I, l.j I i j i ! a ~I H Ix10 - a i 'i t l 000 2 000-3 000 4 000 $ 000 6 000 7-000 8 000 9 000 to 000 12 n a !b! f !i! j ,f 1 8 Downwind Distance (m) I Il df l I!fl Comparison of Atmospheric Dispersion, Factor Calculated with Data Sets from Dif ferent Authors .i l-!;I Figure 1: l: ifrom: Bussian et al., 1980) lh

.. culatiens, the u, certainty due to the dcse conversien factor is, of tainer importance. Assuming a release of ail.Kr 85 during unfavourable meteoro-logical conditions (wind speed of 0.5 m/sec, stability class D), maximum skin doses could reach 320 mrem at a distance of 0.5 miles frca tha stack. In f act, these doses are too low to cause direct health effects such as radiation erythema. As we will point out in'section 3.3., the risk of skin cancer induction will rise statistically. A more extensive investigation is necessary to elimi.9 ate these uncertainties and to give precise information about combi-nation of meteorological parameters, under which beta skin doses of more than 10 mrem could be eliminated with low pro-bability r' errer. With 'the present meteorological models .a.sd dose calculations, there are censiderable doubts that the proposed venting program can exclude the possibility of individual skin doses due to Kr 85 exceeding the 10 mrem limit. A solution of the problem of reducing the individual doses could be venting by a tethered balloon as suggested by dCS. C r, secondly, all persons could be evacuated frem the vicini-ty of the plant during the release. A third solution would be not to release krypton into the atmosphere at all, but.to use alternative metheds of decentamination. 3.2. Cellective doses For health effects estimates, s most relevant parameter is not the individual, but the co lective dose, which is the sum of all individual doses (unit: man-rem). Whereas individual doses can be reduced by elevation of the stack, the collec-tivo dose will remain the same. Assuming a linear dese-res-pense relation, collective doses are proportional to the total health effects caused by the emission. .i t ? I =.--::-.....-...-.=.:=-~......... iv. ..=-u-I 5:# E-ME-W 'J.i.~-N 5D -dE:..-:..;: ='.2?'

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l . NRC made no man-rem calculation. Met Ed has calculated pdpulation dose within'50 miles f cm thefreactor site, ~~ leading to whole body doses of about 1 man-rem. As this value corresponds to whole body dose, the value for col-lective skin dose will be about 100 man-rem within that distance. After' meteorological dispersion, krypton-85 will be found beyond a 50-mile radius, since it has a half-1ife of 10.7 ydars. It will distribute globally and will cause a radiation dose over several decades. The in-tiegrated collective dose will reach its maximum af ter about 70 years when most Kr 85 will have decayed. This means that when in 1980, Kr 85 is released, it will still' con-tribute to radiation deses up to the year 2050. The global collective doses caused by the release of 57,000 curies of Kr 85 can only be roughly estimated. Using a simplified model of global dispersien, the collective dose comitment would be in the ' order of *l 100 man-rem whole body dose and 10 000 man-rem skin dose. 3.3 Potential health effects Little is known about the dose-response relation of krypton radiation, especially about radiation induced skin cancers. Accor' ding to the epidemiological studies summarized in the UNSCEAR report, there is strong evidence that even low ra-diation doses can induce skin cancers (UNSCEAR, 1977). NumerA-cal risk values are very uncertain, as UNSCEAR states: "No good estimate is available for skin cancer induction, but the induction of fatal cancers of skin appears also to be low." The UNSCEAR risk values derived from three different referen-ces do'no*. seem to describe the situation of skin exposure by Kr 85 adequately, since body areas exposed and other cir-I cumstances vary widely.

• ) see e.g. N:RP (1973) and UNS:rAR (1977)
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~ '5 '. 5 ~ h- .TY.-._.....____. . =... f i t 6 4 f a um

I , According.to SEIR report, the absence of further data limits the accurancy of the estimates (BEIR, 1972). The NCRP report en krypton gives no numerical estimates but points out posilble int'eractions between ionizing and ultra-violet radiation. UV'cause's skin cancers. This may be a syner-gistic effecte meaning that small exposures to Kr 85 radia-tion in combination.with UV would have the same effect as a high increase in UV exposure. The NCRP report. concludes: "It is impossible to pre' dict the impact of low-level krypton 85 exposures on the induction of skin cancer by ultraviolet radiation in the absence of direct evidence." (NCRP, 1972) These uncertainties mean that the possibility that the 10 000-man-rem collective dose to the skin may lead to cne additional skin cancer case cannot be excluded. Many essimates have been made of t'he relatien of whole body radiation exposures and they have been the subject of in-tense scientific discussion. ICR2 estimates ene fatal cancer per 10 000 man-rem, or that 100 man-rem whole body radiation would lead to 0.01 fatal cancers. Evidently, ICRP's estimates are at the lower range of values. According to SCHMITZ-FEUER-EAKE et al. (1979), incidence for all cancers and leukemia - is of the order of 0.3 - 1.5 per 1 000 man-rem. MCRGAN's con-- servative l'nterpretation of the results of the Hanford study leady to a maximum value of one additional cancer case per i 140 man-rem (MORGAN, JS79). We therefore conclude, that for the radiation exposure caused by the release of Kr 85, the inducticn of one additional can-car case (probably skin cancer) cannot be excluded. Genetic effects are also expected and are normally assumed to be as frequent as somatic effects. In a summary we conclude that' ,f - population dose estimates of krypten 85 release should be made for a wider area than the 50 miles radius around TMI l j t H i .-~==--=-.m-.. "[ [M '[ "'**L',, .7. --- = - - -. =. - - \\ i b

.c 14 .the global population dose estimates lead only to, approx'i-mate figures. about which there is a considerable uncertainty - numerical values of dose-effect relation for skin cancer induction by krypton-85 beta radiation are very uncertain - no information is available on synergism between krypten ^85 beta radiation and UV radiation in induction of skin cancer - estimates lead to maximum values of one additional cancer (probably' skin cancer) and one case of genetic damage case as a result of the planned krypton-85 release at TMI-2. SensitivitverhadiologicalEnviren= ental. Program 4. In NUREG-d662, the NRC summarizes the projected radiological measurements. We analyzed the program which will be performed by Met Ed, the Commonwealth of Pennsylvania, the U.S; EPA, the U.S. NRC,.and the U.S.. DOE and found that'important in-formation is lacking in NRC's descripticn of the program. Cur critical analysis centers on:

1. the number of locations where measurements are performed

2. the frequency of measurements

3. the detection limits of measurements

4. the importance of "zero-dese" evaluatiens

5. the completeness of exposure pathways

6. the lack' of comprehensiveness in the types of radionuclides considered in the program Generally speaking, it must.be stated that

1. no sensivity analysis is made of whether the location and frequencies of measurements are such that all radiation exposures will be detected. It cannot be concluded that TLD's or dose rate recorders cover the whole area inclu-f f.._.,_

_.,.g, -I u?@\\r+;mwtt.m= v- --i+

..l.,....,..u.

_ - q;; _,m m. .= -...- - = --m :. -.=- :.:- =-.::..- g:..- = . ; = =.= =.:..- = -. ;. -q. - ,. g.;_.. ..;g:g3.g y 1 i 4 I

_ ding the maxilmdm exposed place. Measurements on " pro-jected plume touch-down area during the centrol purge

• will not ensure that the real touch-down area is (NRC) in the measured because of t'he' uncertainties inherent ineteorological models stated *in section 3.1. Although together at least 719 TLD's will be fixed at different locations a considerably smaller number of other' types of measurements 'is projected: e.g. Sr 89/90 analysis 3 locations of air sa=pling filters are only planned at on a quarterly basis by,the " Commonwealth of Pennsyl-vania" program.

2. The frequency of measurements is inadequate. Many TLD's are measured only monthly or quarterly, gas sa=ples are taken only weekly. Thus, higher dose rates that could occur over small time periods will not be detected.

3. In the description of the monitoring program, NRC indi '

cates the detection limit only in one case. Such infor-mation is essential for independent assessment of whether or not the proposed program will ensure all radiation doses. In a study for a Committee of the parliament of the Federal Republic of Germany, the authors analyzed the sensitivity of the official radiation monitoring program in the vicinity of West German nuclear plants. Its results are summari:ed in table 3. It can be seen, that the unsufficient frequency of measurements and high detection limits allow radiation deses, namely those considerably higher than the stated value of one crem per year or even higher than the dose limit of 30 mrem per year whole body dose in the F.R.G., to go undetected. A similar study could be made for the TMI monitoring pro-gram if more information were available.

4. No indicatien is given of.whether pre-release measure-ments are taken for a sufficient time to allow ":ero"-

dose assessment. Variation of daily background exts nal ? h 4 b ]} $ & f ?$3Ek1_=EE& E L ~ ~"~ r : ; Q }===-fi g q Q 4 Q - G Q g l ( i i l.

- -..... "'a' M 3 : Sensivity e' Environnental.v.cnitoring of Radioactivity in the Vicinity of Nuclear Plants (according to standards in West Gernany) v iroms 7 vrz:. et al., ~1980 Cetection limit set by Federal 1,ocati'on and Potential Expesure pathway Ministry of In-Freqency of maximum ra-terior samples diation dose not detected T-dose 10 T1.D's at (e.g. ground site boundaryr excesure) 50 mre=/yr yearly measurement 250 mrem /yr from the samples taken by the li-censee the "indepen-26 mre=/yr (whole body) 7-aerosoles-dent" institution (air) l'0 f01/m? . takes a mix-sample 400 crem/yr (kidney) cuarterly 2 sa=ples per year at farm at area max Cow's milk Conc., (Strentium 90) 0.5 pei/l 2 sa.9eles at dairy 40 mrem /yr (bene) 12 crez/yr (liver) by Co 60/vit 3 12) cow's milk 7 mrem /yr (kidney)

1. Y-nue11d e s) 0.5 eci/1 ibid.

bv cs 137

• • • 2
• E*#

go s milk month at point of .g; 333) max.concentratica 110 mrem /yr 0.5 pci/l and dairy (thyroid, inf ant) several samples vegetables 1pci/kg preferably at area 130 mrem /yr (Sr 90) fresh weight

f max.cencentratien (bene) vegetables 10 pC1/kg 20 crem/yr (T*

.uclides) fresh weicht ibid. (kidt. Cs 137 i t 4 h ^132 --2:=== -+2=Y:E-E:.-. 2 MET ~== =~~~~C2=Mii="*- ~

• ?E+E=i 5~==

^~i %

....:-z--...----....:--.. .,;T - .::.g = ' -- -- " ' " :..= : - =. :; S-l l I hi I 1 h

- - - - ~ - - _'s-. 17 - , radiation, e.g..due to Rn 222 emanation in soil should be considered to detect additional radiation. .S. Important exposure pathways are not considered. At least samples of soil, plants,' dairy. products, etc., should be made. Because of the presence of fallout nuclides En these samples,.zero men'surements are necessary to detect a po-tentialincreasei. As can be seen from table 3, especially for these pathways, detection limits and the frequency of measurements are very important as considerable, doses can remain undetected with'the official reccmmended monitoring program set in the F.R.G. Whole body measurements and urine samples from exposed persons could give additiorial security.

6. Important radionuclides are difficult to detect, particular-ly carbon-14, technetium-99 and other ot.- and 8-nuclides.

'As stated above, 8-n'aclides will not be sufficiently de-tected by the proposed program, especially Sr 90, C 14 and Tc 99. A'alysis ofo(-nuclides is also completely n lacking. To sum up, the proposed monitoring program is not. satisfactory. Most measurements are not frequent enough and are.not made at all in some important localities. Important pathways and nu-clides are' neglected. No indication is given whether and how frequently'zero measurements are made. No analysis is made of the range of uncertainty of the program including detection limits. Thus, th's program cannot en'sure that all significant radiatio'n doses to the community as a result of decontamination of the atmosphere of the TMI-2 reactor building.will be detected. It seems possible that radiation deses that go beyond official limits can occur without being detected. 4 9 H ~ -. =-h.=-hu w :-- .:.yy. -:.....-: =:.w.L= =: ::.

- c g:

7,. .==::,3-3 3;i,: I.:. g: :... :...= j3--.u. : : g=cy.=;cc..:gre,,,,,. -.; gg.- :pg..,,,._.;____. ~ f-i .] i.' a

18 - Acknowledeements We are grateful for the information provided by Daniel /P. Sheehan from the Christic Institute and Bob Alvarez from the Environmental Policy Institute, both Washington D.C. We thank Willi von der Lieth (University 'of Heidelberg) for advise on neteorological models. Gerald Kirchner from the Deparment "of Physics at thd Uni-versity of Bremen provided us with the data on radionuclide inventory of TMI-2 plant. We thank Manfred Hoffmann and Sarah Tocze who helped us with the translat' ion and last but not least Marianne Schmalz who did the typing. e 9 0 0 1 D x + = =- = = = w

=== =+ = w=:-= = =,w.g g 1 l ?

19 - References BEZR= Report, National Academy of Sciences; report of the Advisory Coanittee on the Biological Effects on Populations of Exposure to low level of ionizing Radiationst Washington D.C.1972 (Diaft Report 1979) BMZ - Bundesminister des Innerns A11gemerne Berechnungsgrundlage fQr die Strahlenexposition bei radioaktiven Ableitungen mit der Ab-luft oder im Oberf1Bchenwansert Cemeines Ministerialblats Nr. 21, 15.8.1979 Briggs, C. A. Plume Rise, tl.S. Atomic Energy Comissions Critical Re-view series,1969 Bruland, W.o Erhard, T.o Ern.: s B., Crupp, H., v.d. Lieth, C.W., Matt-o his, P., Moroni, W., Racks, R.,

v. de Sand, H., Sonnhoto V.,

Stcin-hilber-Schwabo B., Teufel, D., Ulfert o C., and Weber, T.s Radio-ecological Assessment of the Whyl Nuclear Power Plant o Capartment of Environmental Protectiono Univetsity of Heidelberg, Heidelbergo Federal Republic of Germany, May 1972 kiruland,W., tranke, S., Teufelo D.; Transfer of organically bound radio-nuclides trough food chains to mant Mode 1= example with radiocobalt and. vitamin B s ZAEA-SM-237/171 Vienna March 1979 r gg Bussian, 'B.M. et al., 'Studie Gher die Auswirkungen mittlerer und schwe= rer Un!B11e im AKW Crohnde !Qt dis Bev61kerung und das Gebiet der Stadt Hameln, Auftrag der Stadt Hameln an das :TZU-Institut !Gr Energie-und Umweltforschung Heidelberg e.V.o Heidelberg, Januar 1980 Cel8, H.,

Vogt, K.J., Ehrlicho H.C.e Polsto, C.t Neuere Ergebnisse von Ausbreitungsexperimenten mit 50 und 100 m Emissionsh6her 12. Jah.

restagung Tachverband Strahlenschutz, Norderney 1978 Killough, C.S and Rohwer, P.S.; A new Look at the tcsimetry of 14 C re= leased to the atmosphere as carbon Dioxides Health Physics 3f (1978) p 151 - 159 Metropolitan Edison Company: Three Mile Island Unit 2 Reactor Building Purge Program Safety Analysis and Environmental Reports Middle-town, November 12o 19791 Responses to 33 questions by NRC of Janu= ary de 1980 Morgano K.Z.1 Cancer and low lefel radiationo Bull. Atomic Science, Sept. 1978, p 30 - 41 f K.Z.; Statement Regarding Release of Kr 85 into the Environment i Morgano } Gf *hree Mile Islands Atlanta, Georgia ) \\ U l 19-E SM ass-SC= T:Wif;ms;m;;;xagmgmmmgm...qqq l i-1 }. l

no 4 .s>.*-

FP, ::acicnal Cc:.:ncil cn Radiation Protection and Measu:ements, Krypton SS in the Atmosphere - Accu.mulation, D1ological Significance, erd contro1 Technology, NCAP Report No. 44, Washington D.C.

1975 ^ NRC - Nuclear Regulatory Connissions Environmental Assessment for Deconiamination of the three Mile island Vnit 2 Reactor Bull-ding Atmospherer NVREG-0662, Washington D.C., March 1980 Addendum I (March 1980) Addendum 2 (April 1980),

Teufel, D., Fran]ce, B., Steinhilber-Schwab, 3 1 Beantwortung der

'3usammenste11ung von Tragen zum Thema Strahlenrisiko* in Auftrag der Enquese-Kommission '3ukQnftige Kernenerg/epolitik* des Deutschen Bundestages, Heidelberg, April 1980 tmion of Concerned Sclehtista lKanda11, H.W. et al.): Deconta ination of krypton-85 from three Mlle Island nuclear plants Cambridge,Kassachusetts, May 25, 1980 VNSCEAR - United Nations Scientific Comittee cn the Effects of Atomic Radiation Sources and Effects of :onising Radiation, Report s New York 1977 WASH-8 400 Reactor Safety Study, An Assessment of Accident risks in V.S. Ccz=ercial Nuc1est Power Plants (N;;AEG 75/024) USAEC, 1975: Appendix V!, Calculation of Reactor Accident Consequen-cess Executive Summary, USNRC,1979 e a b \\; i 2 O g f .~ S;;:;.;:. j l . fG=%E - am+1r=n.+m=. =-==. . n:: s..;=g . -- 2 = : -w_.......... - -._____=.-=.=.=-_=_..-.-----.=:g.=_.w==.;_= =---_ g -. = g. =--. : 3 3.

---

..=.==:-..y.-g; l

. 9

e . 2c'. / N:RP,1:acionsi Council cn Radiation Protect 1:n and Measurements, Krypt _on 8$ in the Atmosphere = Accumulation, Biological Significance, and Control Technology, NCRP Report No. 44, washington D.C.,1975 NRC - Nuclear Regulatory Comraissiont Envirenmental Assessment for Decontamination of the Three Mile island LMit 2 Reactor Bu11= ding Atmospheres NVREG=0662, Washington D.C., March 1980 Addendum 2 (March 1980): Addendum 2 (April 1980).

Teufel, D.,

Franke, B., Steinhilber-Schwab, B.

Beantwortung der ~2usamenste11ung von Tragen zum Thema Strahlentisiko" im Aufttsg der Enquete-Koneission ~2ukQnftige xernenergiepolitik" des Deutschen Bundestages, Neidelberg, April 1980 Union of Concerned Scientist,.(Kendall, H.'. et al.it Decontamination W of krypton-85 from three Mile Island nuclear plants Cambridge, Massachusetts, May 13, 1980 UNSCEAR - United Nations Scientific Co=nittee on the E!!ects of Atomic Radiations Sources and E!!ects of Icnizing Radiaticn, Report New York 1977 WASH-2400 Reactor Safety Study, An Assessment of Accident risks in U.S. Comercial Nuclear Power Plants (NUREG 7$/C14): USAEC, 19751 Appendix V:, Calculation of Reactor Accident Consequen-cess Executive Sursnary, USNRC, 1979 o O s e t .j t t . =. = - _.m-a;;;2,.=.. '=~2_ =33:= = n=.. = =+ =-wan: e= a:am=e=w=.._, --.. C.._.:-s'_--.=.-. i=.3-

---

~g

..g=: ;. :.-_ = :::. ::. :m.-... -........

_ px,-.. 3 35=,.:. :-_ :.= :.= ;;3_ - :., 3 ~ i $}}