“ME | gee 1. Plutonium assay will be by nondestructive analysis whenever ~ possible, employing high-resolution gamma-ray spectrometers with either intrinsic or lithium-drifted germanium detectors. The 64 keV gamma ray from the decay of Am-241 will be the indicator of plutonium. The count- ing system will be calibrated with Am-241-spiked soil samples equivalent to plutonium concentrations covering the range of interest, say 10 to 2000 pCi/g. The activity ratio of Am-241/Pu-239 will be assumed to be 0.4 as reported(in N OR Pg 97 In determining the total Pu activity, Cee the Pu-238/Pu-239 ratio of 0.1 will be used, and no other Pu isotopes will be considered. Each sample will be analyzed (counted) once for a specified time, on the order of 50 minutes. 2. For samples whose Pu concentration is deemed critical to the conduct of Cleanup, analysis will be by standard radiochemical means using an acid-extraction, electro-deposition of unknown plutonium with tracer, and counting by alpha spectrometry. F. PU CLEANUP AREAS. Sample analyses will be correlated with survey data, any on-site FIDLER readings and qualative observations. centrations greater than 40 pCi/g, If no samples yield Pu con- the Pu suspect area will be con- sidered as noncontaminated and certified to be clean. i, readings (greater than 40 pCi/g) are obtained, If any positive they will either indicate