The radio-active xenon and iodine evolved during the dissolution of the uranium may present a health hazard within certain areas around the base of the stack through which the dissolver off-gases are discharged. Since the concentration of these elements in the uranium metal is directly proportional to the power of the pile* and is related to decay period of the metal in accordance with their half-lifes, the maximum rate of discharge of these elements from the stack at H.E.W. can be estimated form existing Clinton data. The required wind dilution to reduce the discharging activation to tolerance levels can then be calculated. The time with respect to the start of the metal dissolution at which the maximum rates of discharge will be attained can also be roughly estimated form existing Clinton data. 3 figs., 3 tabs.