OFFICIAL USE ONLY in polyethylene containers. Concentrations are based on the weight of the material at the time it was received at HASL. Con- sequently, all radiochemical and analytical results are reported here in terms of d/m or grams, per gram of material as received at HASL. Dr. H. Weiss has stated via letter(?) that the wet weights of the plant specimens were not recorded at the time of collection. He has proposed that the results be expressed in terms of d/m/kg of material as received at NRDL. For determination of total beta activity an aliquot of the, solution of wet-ashed material was transferred to a glass planchet, evaporated and dried under an infra~red lamp. Counts were converted to disintegrations by applying a geometry factor based on x40 as a standard. A self~absorption correction was also ap- piied in each case.” Under the wet ashing and plating conditions used at HASL possible loss of volatile fission products such as Ryl06 _ ppl06 is avoided. (3) For practical reasons, the coconut outer and inner shells were dry ashed at 500°C prior to dissolution. * For the particular specimen type under consideration, several values of activity vs. dry weight of the plated aliquot were plotted and a smooth curve fitted for the points. Another curve (based on extrapolation to zero mass) of activity ratio (A/Ao) was drawn and used for determining the self-absorption correction. See Figures 2 through 8.