Effective Retention Time of the Hanford 107 Reactor Effluent Retention Basins

摘要

Studies of the radioactive decay of the gross beta particle emitters in reactor effluent water indicated that the retention time for basins at the different reactor areas varied from 1.5 hours to 4.0 hours for flow rates occurring during the last three years. A statistical analysis of the data from 100-B, 100-D, and 100-F indicated a significant relationship between the two variables, effective retention time and water flow rate. The limited data from 100-DR and 100-H showed no significant relationship. The uranyl nitrate tests, which were conducted at the 107-H West basin by Pile Physics personnel, indicated that a fraction of the uranium passed through the basin in less than one hour and that a maximum concentration was reached in approximately 2.5 hours. This test indicated a more complicated system of flow through the basin than the decay studies had shown and it further explained the large fluctuation in results obtained for the retention time by the decay method. A study of the variation with time of the activity density of water leaving the 107-H basin indicated that a cyclic effect might be occurring in which the variation from the mean was found to be as high as 15%.