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Machine-read from the scan, so expect some errors. Lines that couldn’t be read are left out.
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Bill - It may be tlliit some of my con]lcllts/(lucstiollsare lets dpplicdblc The document gives the impressl n of being much than it actually is. While the assu’nptionsused are stated, the extent of uncertainty or dcgrc!eof conservatism/non-conservatism Is not always Perhaps even more importantly, he validity, reliability and/or limitations of the data base are notcliscussed. This becomes of slgnificant and perhaps critical importance with respect to the gut absorption factor. Although the reported ranges are mentioned, little’in the way of applicability or experimental conditions is discussed (e.g., the reader may conclude that based on the LLL comments a factor of 10-2 should be used for chlovinatcd water, when apparently it is difftc~lt to maintain Pu in the +6 stiItQ under physiological conditions). Si~nilarcomments pertain to other parameters contributing to dose (e.~., coconuts, marine food). It would be helpful for real wqrld decisions to have some idea of the effect of multiple conservatism: upon the final dose estimates (c.g*# 3 11 of wtich is rcspirable, all of which ISmass loading of 100 pg/m , a same concentration and ratio of Pu/ m in SOI1). Perhaps a comparative listing of “conservative” and “real~stlc” vaiues would be appropriate, or at least a table listing the sev~ral conservatism or non-conservatisms.
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1) To what extent, if any, IS the ssun)cddiet realistic or conservative? After what period c]ftime is It anticipated that this diet will, In fact, be available as the prima “y, if not sole, source of food? For example, are the pQople now to ~omc extent dependent upon imported food, and would this continue? obtained from the Rockwell cornplrativesoil sampling program at 13) I{owreliable and consistent is he Pu:Arnratig of 2:1? Is It 1justifiable to assume a 2:1 rat o for both the surface soil (O-3 ciil) and the root zone (0-30 cm)? ~ 4) I{OWrealistic arc the occup~ncy factors stated? Are these valid also spend more time on a village or picnic fsland, but would their estimated dose bc decreased beciusc of avoidance of agricultural islands, increased becau~e they’might be expected to play in the dirt, !sand or coral, or would the dos be essentially the same as for M 5) A gut transfer factor of 3,0 x O-S may not be conservative. EPA recommends 10-4 fulrPU-239, 240 oxide, 10-3 for oxides and non-oxides of other isotopes of Pu, Am and Cm, and 5 x 10-3 for biologically 1‘3for Am is okay, but Pu-239, to say nothing oflPu-23C, absorption f~ctor~ may havo been undcrcstiratcdo
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4subject Is one In which n mbers are ~lven In the report, butThis of the numbers to the Enewetak dose assessments: c) Now significant is Pu-238 dose from marine pathway if transfer factor of 10-3 is used. d) Concentration factors (rati s?) appear very important for coconut meat and milk. To base suc an important parameter upon ~(some of which are lower va ues than “LT” values) raises as to their suitability and;accuracy, (It is incredible :’ . Bikini soil and coconuts ha~e not yet been analyzed; also, presumably ,, t’nothing is known regarding iological incorporation of Pu in coconut c) Is there no 6) Little was said Iabout analytica methods and deviations. plrogressfrom f od, water and air concentrations to dose. .’ It might be informative to understand inhalation/ingestion-body/organ 8) The marine pathway raises a numlcr of qucstlons as to the ’72 survey andi the ’76 survey which probably c n only ? be resolved by additional data. ata are not resolved, and the ues (e.g., the data match global when the ’72 salupleswere bThe conflicts between the two s ts of Ivalues) are not convincing, esp cifilly conducted by 3 labs ond the ‘7G dato is given only by Qtlc, (ss ft to be expected that the Enewcta~ marine life FU values should match those in the Morth Atlantic or he Irish Sea?
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How reprcscntat,lveis a sin’le fish, the mullet. of either t~le Ithink that other fish and t c coconut crab would need to bc sampled before stating that the dosk via marine life Is Inslgniflcaf]t. How vallclare the statement’ (made at the meeting) that tho mullet either between islands or acroGs ocean/lagoon barriers? If t Is not a migratin~ fish, were the ffsh obtained In those area most likely to be fished by the What Is the ba:$isfor the assumption that the mullet is the most direct and rcprcscntatlve 1 nk between marine contamination lcwls It is stated that there is jome uncertainty about what fish t-issue the Marshallese actually iniest. y This sounds difficult to believe considering that we have ha It is true that we really don’t know, why are muscle and skin assumed? Ifthcrc is a dlffcroncc of a factor of O In the 238Pu/239Pu ratios mean concentrations used an why is 3 x 10-5 used as the gut transport On page 8 it Is stated that ~use of 10-3 instead of 3 x 10-5 for to 9.9 mrad/yr. Does this qlso include 238Pu? What if the
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more fiboutthe marine pathw y than WC do the tcrrcstrinl CV* for that matter. the inhalaf~on one. of 10 pC1/g (page 11), how can we consider settlement at Ene~eta~ 10) The uncertainties cjfthe inhalation dose calculations have already pretty WCII been Identified: a) How rcallstic is a mass Ioa’ing of assume that ALL of the r~~uspended to assume that the AMA!3Is C) IS it realistic to assume a!Pu/flmratio identical to that in soil for all rcsplrablc particle$? St seems to me that at least some of thclmass loading would b~ due to particles from ocean/lagoon 1spray which probably havu 1 ttle or no Pu content. 1) It may be misleadlrrgor misir]te~pretcdto retain tables for avera!w soil concentrations up to 400 p i/gin. unreasonably high as an Island ~verage. 2) The use of ~vcri)~~ soil conccntli)tion$IS Iare NOT used, presumably ALL is and areas a delicate one. If averaflcs must be measured, If island
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averages ARC used, iIIdividualvqlues may exceed tho average (alfrostby dcflnition). There probably ar~ two aspects to thfs Issue: parti-lc$il and moral. In terms ofwhut regulatory guidance Is availablu, tile use of averages probably is oka~ assuming that reasonable statistics are occupancy averages, etc. Mltho t the use of averages, the habits and location and exposure of each ll~dividualpresumably would need to be estimated. The moral aspect fs ~more difficult: should anyone need to accept a higher risk than the ‘1 Considering all of the uncertai~tics, my own feeling fs that avct’dgcs are acceptable as long ~s maxim$ similarly ave defined (e.g., a rcsichmce island might have an average of16-8 pCi/gm with no area of the island to exceed, say, 30 pCi/gm). I 3) The above bccomcs ‘tied Into the ~applicablllty of the EPA Guidance to the EneweLak return. This his Iitcrally forced OES to consich’ dose projections from transuran~cs, something that hcrctoforc hud been either not considered or consicl~redto be insignificant. both “considcreds” were in errol. I feel that t.hc,EPA Guidance should be considered to be what it is-{guidance. The closer we can get to or below it, the better off DOE and the Encwotak people will be. However, it is doubtful that CP ‘ will Insist on the use of their Guidance as an upper exposure Iqvel and have {ndi.catedthat 1f It 4can be met we should by all mca s do so, but if It cannot be met the reasons are understandable beca{se of the uniqueness of the sftuation
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was intended for usc in land dcdds, development and USU, and that > these concepts undoubtedly do n t apply to the Enewetak culture. In addition it was stated that ihe Guidance was Intended for U.S. !, but it is not nc cssarily a prerequisite for rQSc?ttlQlilQnt-- [ 4) How all this will help OES within 2 weeks is a mystery to me. Ai~Y ,. ; suggestions or help in determin ng clean-up levels for residence, \ agrfculturc, and visiting islands would be most gratefully appreciatcd~ does the lung dosls,the largest single contributor to the bone dasc! is translocation from the lung. If the inhalation assumptions ore ! conservative by up to a factor ~ f 10, the lung dose becomes qutte + acceptable and the bone dose is reduced iihnostby 1/3. Possible 1 conscrvatiwns in ingestion parallcters(e.g.g concentration ratios) diet estimates miiy lower the bo~e “dose still further; on the other ( hand, raising the GI absorption factor will increase it, The unknowns and uncertainties in the terrestrial and murinc Ingestion pathways I almost preclude any realistic e timates via this exposure route.