6 - 



adequate safeguards. Thus for example we have assumed that the 

 container will not be adequate and will allow imjnediate disper- 

 sion in the water, that all of the radioisotopes produced by 

 Oak Ridge would be placed in one area in the coastal waters of 

 the United States, that the currents and dispersion expected in 

 the area will be the minimum to be expected along the continen- 

 tal shelf, that all of the seafood eaten by some unidentified 

 man would come from this single area, and that this unidentified 

 man would eat unusually large quantities of fish compared to the 

 national average, enough to obtain all of his protein supply from 

 seafood. Even by assuming all of the worst possible conditions 

 it ajppears certain that there would be no hazard if the total 

 annual output of radioisotopes by Oak Ridge were disposed and 

 evenly dispersed in one coastal disposal area one mile square. 

 It seemed unnecessary at the present time therefore to attempt 

 to evaluate the numerous factors of safety in our conclusions, 

 especially since in many cases additional data will be necessary 

 before final evaluation can be made. As a result of these fac- 

 tors of safety, however, it seems highly probable to the commit- 

 tee that the requirements we have established could be relaxed 

 substantially if it becomes necessary or desirable to dispose of 

 larger quantities of radioisotopes in the sea. 



Because of these factors of safety, however, the committee 

 is well aware of the difficulties which will be presented in 

 planning the monitoring program. Since it seems probable that 

 the isotopes will be released from the containers at a much lower 

 rate than we have anticipated and since the coastal non-tidal 

 currents are substantial (as much as 5 miles per day) the de- 

 tection of radioactivity from the disposed material in the sea- 

 water will be extremely difficult. It is therefore apparent 

 that direct counts on the water, or even on crude concentrates, 

 will be useless. The low level radioactive wastes to be dumped 

 in the disposal areas are varied in character and their radio- 

 activity results from an assortment of many different radio- 

 Isotopes. The hazardous nature of the wastes depends on its 

 radionuclide composition. Consequently, not only need the 

 total radioactivity of the water be known, but the Isotopes con- 

 tributing the major part of the radioactivity should be identi- 

 fied. Measurement of radioactivity at low concentrations in 

 seawater is difficult and identification of the radioactive 

 components even more difficult. Large volume samples will 

 have to be processed and analyzed by the best available 

 techniques. The methods are not specified because it is be- 

 lieved that they will Improve with time. The level of radio- 

 activity which should be considered adequate should be comparable 

 to the levels of strontium measured in Atlantic water by Bowen 

 and Sugihara (1957) who determined 6-12 d/mln/lOO 1, by a 

 method which had a sensitivity of about 10~11 [ic/cc (Bowen, 

 private communication) . 



Use of the biological system as a pre-concentrator of radio 

 elements offers promise of value as a monitoring technique. 

 Plankton appears to be one of the most sensitive indicators of 

 radioactivity in the sea (Harley, 195^; Donaldson et_al. , 195^» 



