Chapter 2
PROCEDURE
2.1 SPECIAL REQUIREMENTS AND CONDITIONS
2.1.1 Nevada Test Site Soil. Coral soil is neither physically nor chemically similar to
other widely occurring soils. Also, essentially all fallout data for yields below the megaton
range ha8 come from bursts over NTS soil, which is a more typical soil. To minimize confusion in interpreting fallout results, NTS soil was substituted for coral soil in the expected
crater volume and outside the crater over areas that were expected to contribute debris to
the cloud. For this purpose, over 130 tons of soil from NTS, Area 10, were used at the
Eniwetok Proving Ground (EPG). Figure 2.1 pictures the conically shaped excavation 30
feet in diameter and 8 feet deep that was prepared for placement of NTS soil. This soi)
was compacted to about 90 percent of its measured natural density of 116 lb/ft}. NTS soil
covered the surface to a radius of 35 feet with a minimum thickness of 6 inches.
.2.1.2 Burst Environment. Shot Fig served not only to provide effects measurements but
also to test the warhead.
Diagnostic measurements of warhead performance required that some equipment be located near the device. This instru~mentation together with the standard firing gear used for Operation Hardtack caused the
burst environment to be somewhat different from that desired for simulation of surface
burst fallout. However, only three pieces of electronic equipment were located within the
expected crater radius, with relatively heavy pieces at least 25 feet away. Table 2.1 lists
the equipment used, its distance from ground zero, and its mass. Figures 2.2 through 2.4
show the actual preshot arrangement of equipment around the device. To simulate a contact burst of the weapon, the device was detonated on a light wooden stand, which positioned
the center of the pit 1 foot above the ground surface.
2.2 INSTRUMENTATION
Scarcity of land areas over which fallout could be measured complicated the instrumenta~
tion problem. To estimate the fallout-intensity pattern that would have resulted over an extended land mass, fallout collectors calibrated in terms of full-field dose rates were used
for the major part of the instrumentation.
2.2.1 Layout of Instrumentation Array. The instrumentation array was located according to 146 surveyed points comprising one rectangular and one radial grid system. In Figures 2.5 and 2.6 the array is shown superimposed on the maps of Site Yvonne. The stations
were identified as indicated in the diagrams. There were 92 lagoon stations, 46 land stations, and 8 reef stations established to carry the array.
2.2.2 Remote Area Monitoring System. Two remote area monitoring systems (RAMS),
manufactured by Jordan Electronics, were used in this experiment, one system of 20 units
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