taken around the Rocky Flats, Colorado Plant. EPA samples discussed in the report were those from 1l~cm and 5-cm depth, together with some EPA soil profile sample data. The project was undertaken in an attempt to resolve differences in reported data due to soil sampling techniques employed by those agencies/institutions participating in the project. A discussion is included concerning Cs-137 in soil, with data tables for Cs-137 and Pu-239, Golchert and Sedlet of Argonne National Laboratory presented a discussion of resuspension studies on fallout-level plutonium. Measurements of plutonium concentrations in air calculated at Argonne are compared with data from GMX-5, Nevada Test Site. An Anderson 2000 Impactor was used to collect particles for analysis for comparison of particle size with concentration (distribution) of plutonium. Table I of their paper includes resuspension factors calculated for thorium-228, thorium-230, thorium-232, uranium, and plutonium—-239,240 used in their comparisons. In efforts to characterize environmental transport of plutonium deposited by the Trinity event, a preliminary model for wind movement was discussed by Gallegos, Los Alamos Scientific Laboratory. His paper summarizes dust flux data for a Trinity ground zero site location near the crater along the fallout pathway and examines the relationship between soil and plutonium flux, using analysis of variance and regression analysis methods, Environmental in-field and tm sttu instruments are being developed by Rockwell-Hanford Operations and were reported by Bruns. The systems are designed for use in areas of waste management of radioactive materials. Following migration of radionuclides, identification of contaminated regions, measurement of void volumes (such as potential cave-ins where old waste material was buried and have decayed or disintegrated and may collapse), gas buildup due to radiolysis, density, porosity, moisture content, elemental assay, and down hole radionuclide assay are a few of the uses of the Rockwell instrumentation systems in im sttu situations. Sehmel, Battelle Pacific Northwest Laboratory, discussed measurements of airborne plutonium-239 and americium-241 transport, data obtained from the 125 M Hanford meteorological tower. The experiment was conducted to obtain a better understanding of possible differences in resuspension for the two different nuclides. After measurements of both nonrespirable and small particles at six heights from the meteorological tower, results indicated that plutonium-239 was transported on nonrespirable and "small" particles at all heights. Concentrations of americium-241 on small particles were maximum at the 9l-m height. An apparent correlation was indicated between transport of americium-241 on small particles and plutonium-239 transport on large particles. 747

Select target paragraph3