Table 6 (Cont'd) Sample Collection Date Days Post- Detonation Utirik, pci g t4 60¢, 1255p 1297 137¢5 155ku 12-3-55 12-3-55 11-26-74 11-26-74 11-26-74 9-21-76 642 642 7575 7575 7575 8240 1.9x1071 1.6x1071 2.0x107! 9.4x1072 1.8x107! 1.6x1074 3.5xl07> 4.0x1073 3.7xl107> 5.4x1074 2.3x107> 1.8x109 2.2x109 1.4x109 2.2x109 2.8x100 2.5x107! 2.4x107) - 5-8-77 10-13-77 8469 8627 L.lx1o7! 1.7xl072 9.6x107§ 6.7x107! 1.2x100 - 10-14-77 8628 9-21-76 10-13-77 10-13-77 10-14-77 10-14-77 8240 8627 8627 8628 8628 1.6x1074 1.6x1079 7.8x1071 1.3x1072 - 2.0x1072 1.6x109 5.7x107& 9.0x107! 1.1x1072 - 7.0x107! 1.3x1071 1.1x1079 8.6x1072 2.3x1072 3.2x10° 1.6x10° - - - - 4Multiply by 0.037 to obtain Bq gl, islands after all of the fallout was on the ground. The fallout decay exponent was assumed by us to be -1.2 in order to extrapolate activity present on March 8, 1954, back to activity present on March 1, 1954. The exponent, ~1.2, is the theoretical value for mixed fission products and is considered suitable for estimating the correspondence of I soil results with other measuregents. At Utirik, the fotal fallout activity per unit mass of soil was 7.8 x 10° (0.21 uci g*) at 1.5 days post-detonation. Bq g” The ratio of nuclide activity per unit mass of soil to the total beta activity per unit mass of soil was tabulated in Table 7, column B. This ratio applies at the times of cessation of fallout. The values in column B were compared to values estimated from measurements on actual BRAVO fallout and those estimated by calculation using hypothetical undisturbed fission product yield data. These estimates for BRAVO fallout activity ratios and those for hypotheti- cal undisturbed fission products were determined as follows. 5. The Ratio of Nuclide Activity to Fission Product Activityfor Thermonuclear Fission. Nuclide activity relative to total fission product activity was estimated from data on thermonuclear fission of 2778p given by Crocker (Cr65). Total activity values given by Crocker do not account for chemical and physical deletion or enhancement of fission products, production of activation products, Or production of transuranics. Total activity per 10,000 fissions at 0.5 and -14-