All] samples were oven-dried, ground and a portion compressed in polyvinyl chloride (PVC) pipe 2 inches in diameter and either 3;"or 1" inch deep that was used as a sample holder for radionuclide measurement. Fifty grams of tissue or 68 grams of soil could be compressed into the 2" x 1" container. The density of the biological and soil samples was 1.0 and 1.35, respectively. samples were then analyzed for gamma-emitting radionuclides, These The gamma-emitting radionuclides in the samples counted on the NaI crystal were determined by a method of least squares. The radionuclides values in the samples counted on the Ge (Li) detector were calculated by hand or with a computer by adding the counts in five channels under a peak in the spectrum,subtracting the appropriate background counts, and applying correction factors to convert counts to picocuries (pCi). A set of previously reported reference Spectra for the different geometries and radionuclides were used. were corrected for decay to the date of collection. Al] values Iron-55, Strontium-90 and Plutonium Analyses pol vent extraction, electrodeposition, and X-ray spectrometry were used for 5°Fe determinations. To measure 90sr content, 20Y was chemically separated from 90Sr, collected on a filter paper and counted with a low-level beta counting system, Plutonium was extracted by ion exchange, electroplated on platinum discs, and analyzed by alpha spectrometry with systems using surface barrier alpha detectors and pulse-height analyzers. use of 242py as a tracer. Chemical yield was determined by Error Limits 90 For a single sample, the error given for all radionuclides listed, except Sr, 55Fe and 239,240pu, are two-sigma, propagated, counting errors. The error values for 29Sr, 55Fe, and Pu includes the two-sigma counting error and an analytical error, The error term for more than one sample is one standard deviation and disregards counting error. Limits of Detection Many factors influence the limit of detection, including the type of de- tector and analyzer, the presence of other radionuclides, the duration of the counting period, the size and density of the sample, and the geometry relationship of the sample and detector. Hence, the limits of detection varied consid- erably for various radionuclides and types of samples, but can be summarized by stating that the detection limits were approximately as follows: By gamma detection 40, 2.1 pCi/g or less 238) 0,41 102m, 125 137, 152, 155 2075, 2355241 » Sb, s, Eu, ~~Eu, Am " i 0.12 pCi/g or less By beta detection 905), ).2 pCi/g or less DOF yee pyobo .