goat by Stanley and Mullen, the curium was excreted more rapidly. Shortly after injection, the percentage of the administered curium dose in the biological samples was higher than the plutonium values, based on percent per kilogram basis. Sutton et aZ. also reported on an investigation of transport and retention of 238py in calves fed in vivo labeled milk vse prepared in vitro labeled milk. This experiment will provide information on the relative biological availability of plutonium in the two experimental groups of animals. The cows which received the citrate-buffered plutonium-238 nitrate were also sampled for uptake. Results of these experiments will be provided in a future NAEG document as data were not available at the time of the reporting session. Small vertebrate investigations for NAEG are performed by University of Nevada, Las Vegas (UNLV), at NTS and the Tonopah Test Range. Data on rodents and lizards from NAEG safety-shot sites, NTS, are presented in this report. Moor and others at UNLV reported lower carcass burdens of 233pu and “41am than pelt or G.I. tract burdens by a factor of 102, Hematologic studies of rodents from the NTS and TTR areas are currently under way. Methodology and preliminary analyses are discussed. Moore et al. report that some of the changes in NTS soil chemistry environments may be due to animal burrow environments. They suggest that soluble nutrients, gases, humidity, and temperatures are at levels which are more conducive for maintenance and growth of microorganisms than surface soil areas. Animal burrows, of course, are difficult areas to study in that many factors are involved. Mechanical stabilization of burrow areas for easier sampling (e.g., freezing tunnels for easier and more discrete soil samples), sampling that is meaningful, individual species of small vertebrate habits study, biological inventories of microhabitats, and food sources are a few such factors, not to mention radiochemical variance in differing environments. Preliminary synthesis of some of the data generated in the various safety~shot areas studied by NAEG has been begun by several investigators. Until recently, field measurements of the concentration of Pu in various ecosystem components were the primary objective of most of the NAEG investigations as a beginning step toward providing information for an ecosystem model for the transport or movement of Pu in the environment. Gilbert, NAEG statistician, presents efforts by several of the NAEG program investigators to synthesize the 239°240pby data currently available from Area 13, NTS (an NAEG safety-shot study site). Data on soil, vegetation, small vertebrates, large vertebrates, and air concentrations previously reported are combined within single graphs in order to evaluate trends or information not obvious by other means of presentation. The limitation of few numbers of animal data from the Area 13 grazing study to date causes restricted interpretation. However, it is evident that the lowest concentration in cow tissues is in muscle, and the highest in hide and hair. Statistical analysis indicates that lung concentrations 320 uy