~ Ye reliable estimates (see pg. 561, ref. 3) for these average yearly exposures were 6.3 rads for 1953 (from the fission yield) and 1.6 & 5.9 rads for 1952 (from the fission-yield and air beta activity, respectively). For 1955 and 1951, I only have my estimates of 2.0 and 0.4 rads from the fission yields of 84 and 18 kilotons during the growing season (see pg. 561, ref. 3). Comparing my approximate fission yield estimates of dose with more reliable methods suggests that the fission-estimates averaged over a year of testing might be accurate within a factor of 10. Therefore, I have assigned dose ranges of 0.2-20 rads for 1955 and 0.04-4 rads for 1951. It is not my intent to deceive the reader into believing that the true doses are well established for the years 1955, 1953, 1952 and 1951. More work is needed. My best estimates of the average thyroid doses for all Utah infants is summarized in Table 1 for each year of Nevada testing. much higher: Individual doses were Knapp estimated doses of 120-440 rads for infants in St. George, Utah, following the "Harry" shot of 19 May, 1953°). ‘the dose for our high est station in 1962 was 9-26 times greater than our average @) . ESTIMATED AVERAGE THYROIDDOSES TO ALL UTAH INFANTS YEAR OF TESTING 1962 RADS LOWER HIGHER LIMIT LIMIT Q.63 - METHOD OF DOSE ESTIMATION Q.77 S.L. MILK POOL & PENDLETON’S MILK STA. 1958 0.2 USPHS SALT LAKE MILK POOL 1957 1.3 USPHS SALT LAKE MILK POOL 1955 0.2 - 20 FISSION YIELD 1953 2 - 12 FIELD BETA ACTIVITY AFTER SHOT "NANCY" 1952 3 - 18 FIELD BETA ACTIVITY AFTER SHOT "EASY" 1951 0.04 - 4 FISSION YIELD Next I tabulate the total number of exposed Utah infants, and compute the average dose for all of them (Table 2). from the U. S. Census (1960 & 1950). The yearly births were derived The average birth time was taken as mid- year, followed by an average delay of about 6 months before appreciable consumption of fresh cow's milk. Thus, exposures were regarded as starting during the calendar year after the calendar year in which birth occurred.