field until the maximum dose rate was reached or until slightly less than half of the assigned time had elapsed for short recoveries. They would then return toward the starting
point, recovering sticky pans and monitoring until maximum time allowed in the field had
elapsed. Back at the starting point, dosimeters were read, a new and smaller allowable
dose calculated, and a new recovery entry planned.
2.3.4 Lagoon Recovery Parties.
Five LCM’s boats and one DUKW were used by the
lagoon recovery parties in collecting buoy sticky pans. A water taxi was used to transport
personnel to the barges. All parties entered the fallout field by H+ , hour.
2.3.5 Sticky-Pan Counting. Sticky pans collected from the fallout field were brought to
the counting tent at Station 1520 by helicopter, water taxi, LCM, DUKW, weapon carrier,
and jeep.
Pans were laid out on a large concrete pad marked with the same coordinates as
used in the field and were systematically brought into the tent for counting throughout D-day,
that night, and D+1.
2.4 REQUIRED DATA
2.4.1 Full-Field Dose-Rate Calibration. The original plan for calibration of sticky-pan
data in terms of full-field dose rates was as follows: Recordings of full-field dose rate
versus time from each of the fixed RAMS stations on land were to be associated with graphs
of average count rate versus time for the sticky-pan cluster at each of the stations. The
full-field dose rate corresponding to any sticky-pan count at any time could then be determined. To minimize the effect of fractionation and collection efficiency that might depend
upor location in the fallout field, calibration obtained from a given RAMS station was to be
applied only to sticky pans collected from nearby stations.
A similar procedure was to be used to calibrate buoy sticky pans. In this case, the
average of the readings from the cluster in front of each barge was to be compared with
dose-rate readings at the center of the respective barge. Dose-rate readings were corrected to full-field readings, where a uniform deposition of fallout on the barge was assumed. Corrections for nonuniformity could then be made from barge sticky-~pan data.
The ratio of the dose rate measured with a survey instrument at a sticky-pan station
near the shoreline to the full-field dose rate indicated by the sticky-pan count at the same
H~plus time would then be a measureof the fraction of full field at that location and could
be used to correct other survey readings taken at comparable locations. Because of developments that could not be anticipated, several changes were madein the calibration procedure. These changes are discussed in the next chapter.
2.4.2 Air Samplers. Filters from the air samplers were counted in the same geometry
used for sticky-pan counting. By relating the count rates of filters and adjacent survey
meter and sticky-pan readings, an estimate of the contaminant mean fall rate was obtained
by using Equation 1.5.
2.4.3 Wind Measurements. Winds were measured by manual tracking of free~rising
balloons with two Signal Corps PH-BF33 Akeley phototheodolites. Locations of the phototheodolite stations and the remotely controlled balloon release stations are shown in Figure 2.16.
2.4.4 Cloud Dimensions. Cloud photographs were obtained from three camera stations
located at positions shown in Figure 2.17. Stations on Wilma and Elmer were atop 75- and
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