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RADIOLOGICAL CLEANUP OF ENEWETAK ATOLL
There is much cumulous cloud cover. 1 moderate rainfall of 57 inches
mean annually, and fairly constant northeasternly trade winds of 0 to 30
knots. A wind rose is shown in Figure |-18.
Most depressions, tropical storms. or typhoons occur in the months of
September through December. although they are possible at any time of
year. Typhoons are not common but do occur. resulting al times in severe
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10% of readings
Ca) 11-21 knots
Wind directions (given in degrees) are along vectors and from
outer end toward the center.
25% of all wind velocity readings are at 10 knots or less.
Percentage of readings of velacities of 11-21 knots are
indicated by length of vector, e.g, 35% of the time, winds
of 11-21 knots will blow from ENE (67149).
FIGURE 1-18. ANNUAL AVERAGE WIND DIRECTION AND VELOCITY.
HYDROLOGY
Enewetak Atoll must rely upon rainfall as its only source of fresh water.
As the soil is extremely porous, drainage of rainwater by downward
percolation takes place rapidly. The percolated water interfaces with the
marine groundwater that has infiltrated through the porous rock from the
sea and lagoon. Fresh water, when poured on an open bodyof salt water,
spreads rapidly over the surface of the denser salt water and the two
become thoroughly mixed through current and waveaction. Porous rock,
such as that found under the islands of Enewetak, imposes an obstacle to
this rapid spread and restricts the mixing. On a roughly round-shaped
island of uniform permeability, the body of fresh water floating upon the