In these evaluations, it should be enphasized that dosages through various pathways are estimated on the basis of environmental data and considerations of expected living patterns and dietary habits. While “radiation standards" do not exist for environmental contamination levels in substances such as soil and foodstuffs, there is general agreement in terns of conservative models of these pathvays and the relationships between a certain level in the environment and the likely dose to result from the pathway exposure. The area of plutonium in soils, however, is one for which there is no general agreenent as to the quantitative relationship between levels in soils and dosages to be expected throuch the inhalation pathway, the primary one throuph which man can receive a significant dose fron plutonium. The ICRP recommends a maxinun permissible average concentration (IPC) of 1 picocurie per cubic meter (pCi/m?) of air for "insoluble" plutoniun and 0.06 pCi/m> for "soluble" plutoniun for unrestrictel areas. While the plutonium in the soil at Eneweta is thought to ba typical of world-vide fallout, and thercfore insoluble, 9.06 pCi/n? will be used for the sake of conservatisn. Appendix A of [Cnevetak Radiolovical Survev, ‘1VO-140, presents two possible methods for deriving the exposures that may occur tiurough the inhalation pathway for pluteniun in soil. (This is the pathwav of interest for the present although it is reorganized that for the very distant future, ingestion may become more important by comparison. Table 250 of Appendix ZI shows that exposure to bone, liver, and lung from 239Pu are expected to be a few hundredths of a ven in 30 vears for pathways other than inhalation.) Thies material is produced as Attachment I of this section. i24-40