restrictj:d 



3 



At the end of two days the strip of contaminated water 

 will extend froiu Bikini Island to the southv/estern passes and 

 will be about two miles wide. The maximum concentration in the 

 eastern end v/ill be less than 1% of the initial value and in the 

 western end about 1 X 10~5'J3, 



It is difficult to cariy the analysis beyond this point, 

 but it is certain that further dilution will take place at a 

 much slower rate, and it will probably require a week or two to 

 reduce the maximuid concentration to O,lfo of its original value. 



If the v/inds were only 5 knots instead of 10, three or 

 four days would be required to establish the condition de- 

 scribed. If they were 20 knots, it would require about a day 

 and a half. It is not possible to predict accurately what would 

 happen in the case of flat calm or wind directior other than 

 easterly since neither has been observed. It is certain, however, 

 that the above predictions would have to be modified. It is 

 probable that with several days of c alia weather, the internal 

 circulation of the lagoon would be destroyed and that radio- 

 active products would be spread only by tidal currents and a 

 very slov/ horizontal diffusion. V/ith southerly winds, on the 

 other hand, it is possible that the lagoon circulation would be 

 accelerated by increased inflow through Enyu Channel. 



After the second day contaminated water will begin to 

 leave the lagoon by a series of ebb tide pulses through the 

 southwestern passes. The amount leaving the lagoon will be very 

 small at first and will increase during the first week or so 

 to a maximum value of about 3!^ of the total contaiainant in a 

 day's time. Thereafter the rate of loss will be about 3% of the 

 remaining contaiuinant per day. 



