RESTRICTED 

 23 



contaminant would reniain in the target area and the latter 

 would be unsafe for re-entry until wind currents were again 

 generated. 



A southerly or southeasterly wind would change the direc- 

 tion of the lagoon circulation but otherwise would not change 

 the previous description of the spread of radioactive products. 

 It seems possible although by no means certain that the rate 

 of flushing of the lagoon would be drastically altered if 

 southerly winds persisted long enough to alter the direction 

 of the oceanic current outside. The most likely guess is that 

 water would then flow in constantly along the full length of 

 Enyu Channel at a rate of about 10% of the lagoon volume per 

 day and would be flushed out by tidal interchange across the 

 northern and western reefs and through the southwestern passes. 

 This Would rapidly clear the target area and triple the observed 

 rate of flushing. 



Veering winds during or after the tests would alter the dir- 

 ection of flow of the currents so that the path of contaiainated 

 water would no longer be a straight line across the lagoon and 

 back. This would increase the horizontal spread of radioactive 

 materials, and the rate of vertical diffusion would be maintained 

 at the initial high level for a longer period of time. The net 

 result probably would be that the rate of dilution during the 

 first few hoxirs or the first day would not be greatly altered 

 but that subsequent dilution would be greatly accelerated. 



3 



