OPERATION HARDTACK I - DATE: TIME: PPG Time 6 Aug 1998 i15 Quince GMT Sponsor: 6 Aug 1958 0215 SITE: UCRL - DOD PPG - Eniwetok - Yvonne 11° 33’ 162° 21' 15" ok" Site elevation: HEIGHE OF BURST: N & Sea level 3 rt TYPE OF BURST AND PLACEMENT: Surface burst rrom platform CLOUD TOP HEIGHT: 1,500 ft MSL CLOUD BOTTOM HeIGHT: NM on coral soil REMARKS: Only alpha contamination resulted from this detonation. Surface alpha monitoring was conducted throughout the area on D and Dtl day with PAC-3G gas-flow proportional alpha counters. The readings were taken in counts per minute, corrected for the probe area, and multiplied by the appropriate shielding factors to compensate for the roughness of the surface monitored. The two isoconcentration lines shown are the most significant ones, since 3,500 pe/m® is the chronic hazard limit and any concentration in excess of 1,000 ue/m? requires decontamination. It is interesting to note that in the great majority of cases the alpha concentrations in the downwind area were higher on Dtl than on D day. 308