the chromatogram at the time the collection of the fraction was begun, Analysis of the decay data for the first four fractions of Sample 4-3 (Shot 4, third eluticn run) of the chromatogram is shown in Figs. B.2 through B.5. Since Sample 4-3 did not contain sufficient Na activity to increase the count at the Na breakthrough (Fraction 4-34), the analysis of the decay of Fraction 4-24 from Sample 4-2 which did show Na activity is given in Table B.1 and is plotted in Fig, B.é. 4-2 was run about 24 hr prior to Sanple 4-3. Sample When the elution of Frac-~ tion 4 did not give an activity peek, the fraction was not further analyzed for Na<4, The spectra of the five fraction» at various times are summarized in Table B.1; only the major photon peaks are listed, The probable radioactive constituents of the first five fractions are given in Table B,2,. The first. or anion fraction, contained the iodine activities and also activities from the insoluble (acidic) elements Ru, Rh, Te, Tc, and possibly some Kio, The relative amounts depended, of course, on time after burst when the elution was made and on the pre- treatment of the sample. The elution of fallout sarples from the island shot which were dissolved with strong HCl and diluted to pH 5 generally gave smaller peaks for the water wash which, in turn, contained relatively smaller amounts of the insoluble (acidic) elements, However, small anounts of these materials tailed along into the HCl elution until the alkali Fraction 4 where Ko?? peaked along with the alkalis. The Te (Fraction 3) usually gave a higher peak than that shown by the chrom- togram = especially at earlier times, The Np (Fraction 1 and 2) usually contained less Te impurity than that shown in Table B.1., At +3 to +5 days, when the Np activity reaches a maximum percentage of the total activity, it was often difficult to detect the Te (or other) impurity in those fractions. When the fallout sample was treated with a reducing agent prior to adsorbing it on the colum, the Np peak did not appear. The alkali elements (Fraction 4) then came off first in the acid elution, Hence, the Np in Fractions 1 and 2 must be in the +5 (or +6) oxidation state, The general double peaking of Te, and perhaps. of Ru and Mo, first in the water wash and again later at different places in the HCl elution, seems to indicate a distribution of oxidation states for these elements, First, they did not tail off in the usual manner, and secondly, radionuclides of each element appeared to have fractionated to some extent. Since the stability of the chlcride complexes and the acidic properties of Ru, Rh, Te, and Mo depend upon the oxidation state of the element, the latter would therefore determine the ion exchange behavior, Further exploitation of ion exchange methods in the analysis of fallout materials in future field tests such as this would be extremely useful in the detailed characterization of the contaminant the important radioactive constituents. Aad especially for