CHAPTER 3
EXPERIMENT DESIGN
3.1
INTRODUCTION
It was evidently necessary to correct in the Operation CASTLE
studies some of the experimental difficulties axperienced at IVY and to
extend the scope of the investigation. In order to minimize the contamination of inactive particles by active solution and to avoid
collection of excessive amounts of.extraneous dust and rain, a new
system was devised for collecting fallout, which is described below.
The range of particle size under investigation was extended downwerd
to 5 p.
This operation provided three types of detonation: sunface land,
surface water, and intermediate. Unfortunately operational difficulties
prevented an adequate comparison of effects from the different types.
It was originally an objective cf this project to study base surge,
bat the base surge collecting stations were destrc¢yed, as reported by
Wilsey and co-workers.
3.2
3.2.1
FISLD INSTRUMENTATION
Teo-Phase Fallout Collector
This collector was essentially an inverted cone, 2 ft in
diameter at the base, and 2 1/2 ft in height (Fig. 3.1). The cone was
equipped with a dust-proof and water-tight cover which slid oven when
a signal was received, remained open for 5 hrs, and automatically slid
shut. Approximately 4 liters of a solution of carbon tetrachloride in
chlorobenzene (one part carbon tetrachloride to five parts chlorobenzene) were placed in the bottom of the collector. Ona liter of
aqueous solution containing 0.5 per cent Aerosol OT and 0.125 per cent
Versene was stored in a container mounted on the side of the collector.
A delivery tube from this container extended into the collector and
was stoppered with a cork connected to the cover of the collector (Fig.
3.2). When a signal Was received, the cover opened retracting the cork
from the delivery tube. Tha aqueous soluticn flowed onto the heavier,
{rriscible organic liquid. When fallout arrived at the collector, all
16
SECRET — RESTRICTED DATA