UNCLASSIFIED that none is removed with the stripped solids. Confirmation of this was obtained by dissolving the acrylic film strippings in organic solvents and examining the solutions for insoluble gelatin pieces; none were observed. Both the stripped reagent film and the removed solids were counted in a crystal well counter. Sixteen percent of the activity remained on the reagent film. This represents short-exposure, water-soluble activity together with certain colloidal size solids below the visible range of the microscope. Each of the many other fallout particles with its chloride reaction area was cut from the reagent film. The photon activity was then assessed in the crystal well counter containing a 2-in. NalI(T1) crystal with a sample well 3/4 in. in diameter and 1-1/2 in. deep. The counting efficiency for fission products is in the region of 40 percent. Decay and coincidence loss curves were constructed for the instrument using early time fallout, enabling activities of individual particles to be reliably corrected to H + 12. EXPERIMENTAL RESULTS The condensed and averaged data of Flathead and Navajo are presented in Table 1, The data are grouped in increments of time of arrival at the various ship stations. Some of the particles measured for one variable were not measured for others. Thus a maximum and minimum number of particles measured is sometimes reported for a given time interval, It was found in general that the insoluble solids comprise less than 4 percent of the weight and less than 2 percent of the volumeof slurry droplets. Therefore, in the size and density considerations this com- ponent was neglected. It was assumed that the water present in the slurry particles was saturated with sodium chloride, The fact that dis- solved sodium chloride occupies about 19 percent less volumeina saturated water solution than does an equal weight of dry crystalline sodium chloride was considered in the calculations, The activity is primarily associated with the insoluble solids, Since no precise measure of mass or volume of this component is available, activity as a function of sodium chloride mass is reported. Estimates were made of the specific activity of the insoluble solids, One method involved the direct stripping, weighing, and measuring of activity of solids from a reagent film, Another method involved the -6- et we k hi pa Pi FA 4 mq po rd “ Ba pea Ra UNCLASSIFIED