OPERATION HARDIACK I - | TATE: TIME: PPG Time Dogwood GMT 6 July 1958 0630 Sponsor: 5 July 1956 1830 SITE: UCRL PPG - Eniwetok - SW of Janet 4,000 ft to nearest edge of island (Sta. 1312) 12° 39! 162° 13' HEIGHT OF BURST: 48" 48" N &E 12.25 ft TYPE OF BURST AND PLACEMENT: Surface burst from barge CLOUD TOP HEIGHT: 58,000 ft MSL CLOUD BOTTOM HSIGHT: on water 25,000 ft MSL REMARKS: Only individual island dose rates are available. These were obtained from Radiological Safety organization helicopter surveys at H+ hours. The helicopter survey technique called for the pilot either to land the aircraft at the desired spot, so that a ground reading could be obtained, or to make a slow pass over the desired spot at an elevation of 25 feet. Readings taken at 25 feet were multiplied by a factor of 2 in order to obtain a reasonable approximation of the true ground reading. The basic instrument used in the aerial surveys was the AN/PDR-39 survey meter modified to read up to 500 r/hr. The t-1:? decay approximation was used to extrapolate the H+4 hour doserate readings to H+l hour. 282