APPENDIX IV 



AN ANALYSIS OF DISPERSAL OF RADIOACTIVITY FROM LOCAL 

 SOURCES ON THE SEA BED * 



R. O. Reid 



INTRODUCTION 



The purpose of the following analysis is to establish upper limits on the 

 concentrations of radioactivity which migjit occur in sea water under certain 

 prescribed conditions of sources on the bottom in the relatively shallow water 

 regions of the continental shelf. A number of assumptions must be made in 

 regard to the diffusive properties of the water, the currents and the character 

 of the sources. In all cases the assumptions utilized are deliberately taken to err 

 in favor of large concentrations . In other words , the intent of the present analysis 

 is not to give an acciarate description of the diffusion processes but to give some 

 limiting values of concentrations in the sea under the most extreme conditions 

 which can be visualized. 



The following stipulations apply throughout the present analysis : 



(a) The radioactivity of the sea water is not depleted by adsorption of the 

 radio isotopes on the bottom, 



(b) The natural decay of the isotopes is neglected (i.e. , tlie radioactive half 

 life of the isotopes is considered infinite) . 



(c) The diffusion process is considered to be Fickian (i.e. , tlie diffusivity 

 coefficient is isotropic and uniform throu^out the sea water ) . 



• Contribution from the Department of Oceanography and Meteorology of 

 the Agricultural and Mechanical College of Texas , Oceanography and 

 Meteorology Series No, , 



