Experimental studies on the deposition to crops of radioactive gases released from gas cooled reactors. Pt. 1: Carbonyl sulphide-35

Experimental studies have been performed under controlled environmental conditions to determine the velocity of deposition (Vg) of CO35S to crops, in order to validate mathematical models developed by Nuclear Electric for use in relation to emissions from its gas cooled nuclear power stations. The effects of a spike release at different growth stages was determined for wheat, bean and cabbage. After measurement of the Vg the fate of the 35S in individual organs of the crop was determined by sequential measurements upto harvest at maturity. Deposition velocity measurements ranged between 0.002 and 1.104 cms-1, dependent on plant size. Correction of Vg for plant weight may prove to be more appropriate for model validation. The allocation of the 35S within the plants generally followed the growth patterns of individual organs. Loss of 35S from the crops was almost entirely explicable in terms of radioactive decay. (author)