currm 2 ! FINDINGS eee 2 The similurity of ths trends of radiation intensity and settled dust activity ie obvious from the table. Gamma intensity should be roughly proportioned to cumilative settled activity, on the premise that the Sointilog readings were due entirely to rudiation from the ground = -face, but we have no cewe* baeke for predicting radiation inteneities from fallout AERIAL MONITORING The flights made according tu the plan described in Chapter 1 are mapped tc Figures 2,1 and 2.2. The radiation intensities are showm on the maps md also, to permit identification of the ielands, in Tables 2.2 and 2.3. At places where no data are given the rates are Jess than 0.05 mr/hr. The highest value was 1.5 mr/hr on M plua 3 at Agrihan the in the Marianas.. Gm the basis of the decay lav usually assumed, with an exponent of minus 1.2, the cumulative dose to the population of this poland was est'mated at 500 milliroentgens, neglecting the possibility that rain might wash away the active dust or concentrate it onto limited areas, The smount washed off can- not be guessed but the process must certainly occur and the estimate of the dose to the general population is therefore conservative. Some such process evidently reduced th+ radiation level on a number of islends in the lower Mortenas from 0.5 ar/hz on M plus 3 to an undetectable amount on M plus 5. Settled dust sampling stations had deen established at some of tha islands included in the serial survey. ‘There were two such stations on Guan, an island on which relatively high radiation intensities were found during the week a“te” MIKE shot. The serial monitoring results and th. duplicate wettled dust data for this period at Guam are listed in Table 2.1. ; 1 TABLE 2.1 RADLATION INTEMS:9° AND SETTLED ACTIVITY AT GUAM Casmen Settled Dust Activit (efor) att. 1.0 0.7 0.5 280000 14,000 27000 1000 0.1 1600 0 100000 (12 are} 697000 (12 hrs eGempling period was 2 hours, except where noted. Data are extrapolated to the day of sempling. *lo sampling during this 10 hour period, a wba