Equations 6, 7 and 10 then become 

 (20) s (t) = 16 — „ 



(21) tpp^ = 4 



3.5 X IQl' 

 (22) N < 



M 



ppc 



M 



ppc 



. t 



ppc 



The resulting computations are summarized in Tables 13 and 14. 

 Table 3 shows that the predicted activity on the spent ion exchange res- 

 ins for the SAVANNAH* is about 400 curies. The weighted mean ppc 

 value for fishing areas of the open sea, for the isotope mix on the ion 

 exchange resins of the SAVANNAH, is about 5 x 10"^. Applying this 

 value to the subject open sea area, equation 22 gives a limiting value 

 of over lO' for the permissible number of releases, per month, of 400 

 curies each. This corresponds to about 30 such discharges per day. 

 In those large areas of the open sea which do not contribute materially 

 to the commercial fishery harvest, the appropriate value for the corre- 

 sponding environmental ppc is 3 x 10"'' . The permissible number of 

 releases into the subject open sea area would for this case be over 

 10^ per month, or 300 per day. Thus, if each of the 300 potential nu- 

 clear-powered ships should discharge spent ion exchange resins, con- 

 taining 400 curies each, into the subject open sea area once each 2 

 months, the permissible limit of radioactivity in the environment would 

 not be exceeded. 



CONSERVATIVE AND NON- CONSERVATIVE ESTIMATES USED IN 

 THIS REPORT 



As a result of the many gaps in our basic knowledge of the per- 

 tinent phenomena in the sea v/hich enter into the problem evaluated in 

 this report, it has been necessary for the working panel to include 

 many estimated parameters in the evaluation. Because we are treating 

 a problem which is potentially very dangerous to man and to man's 

 utilization of the natural environment, we have in general made con- 

 servative (safe) estimates of the uncertain factors. An additional rea- 

 son for making conservative approximations is that the nuclear ship 



*Since completion of this report, subsequent re-evaluation of the probable character and 

 activity of the primary coolant and the ion exchange resins has been issued by the Oak 

 Ridge National Laboratory (1959). While this ORNL report includes somewhat different 

 values for the activity in these potential wastes, the general conclusions arrived at here 

 remain unchanged. 



45 



