a. the fact that 5, 10, 15 and 20 roentgen intinity dose fall-out areas are shown in the Figures, it appears that in some farming areas the Strontium 90 concentration may be as hizh as 0.5 to 0.75 curies per square mile from one shot. In areas where the fall-out from several shots are superimposed, the concentration could be higher. However, it is more significant to note that the areas wnere there is appreciable concentration of Strontium 90 are relatively large. from 1000 to 5000 square miles for each shot. These areas range for greater details con- sult the figures and the information contained in Table I. It seems apparent to the writer that the immediate area of the Test Site and the farming comminities in the periphery of the test site (within 150 miles) may be examined profitably to determine the uptake of fission products by plants and animals, and for the effect af fission products on relatively small water supply sources. It is hoped that the radioactive fall-out areas indicated in this report would be useful along these lines of endeaver. The experience gained in this study indicates that in or- der to determine the world wide contamination pattern or even the percentage fall-out of rasidual activity in the Jnited States relatively large number of sampling stations must be utilizad. As indicated in Paragraph II, F above, when tha fall-out covers @ Large area and if the intensity of the readings are low, there igs a tendency to overestimate the percentage fall-out. activity. This is even more so in the case wher) rain brings down if such readings are averaged ovar large areas by the use of hh en dee planimeters, the percentage fall-out msy7 52 highly exaggerated, C3-36417