Preliminary DCGLW for surface soil of Kori Unit-1 decommissioning site according to habit data and age of human receptors

Abstract

The preliminary derived concentration guideline level (DCGLW) for the surface soil of Kori Unit-1 was calculated considering the habit data of residents living near the nuclear power plant in South Korea (a 1-y-old infant, a 10-y-old child, and an adult), following the ICRP 101a recommendation for radiation protection of the public. The radionuclides of interest were 3H, 14C, 60Co, 63Ni, 90Sr, 134Cs, 137Cs, and 241Pu. 14C, 3H. 14C, 3H, and 241Pu had the maximum total effective dose equivalent (TEDE) after a certain duration, whereas 60Co, 63Ni, 134Cs, 137Cs, and 90Sr had the maximum TEDE in the first year. In the initial period, 60Co, 134Cs, 137Cs, and 90Sr had the most dominant effect on TEDE in all the age groups, but their influence disappeared after 203.09 y and only doses of 241Pu and 90Sr were observed thereafter. The main exposure pathways of 60Co, 134Cs, and 137Cs were external pathways, but the main exposure pathways of 90Sr were plant (water-independent), meat (water-independent), and milk (water-independent). The maximum TEDEs caused by 60Co, 134Cs, and 137Cs were similar in all the age groups, but that caused by 90Sr considerably varied depending on the age group. The nuclides for which the DCGLW was notably different from the conservative DCGLW were as follows: 3H (increment of 109.21% and 183.08% for the child and adult, respectively), 63Ni (increment of 286.37% and 702.86% for the child and adult, respectively). The main exposure pathways for these radionuclides were ingestion pathways (water-dependent or independent), which led to internal exposure. The findings can provide insight for the considerations of the human receptor to calculate the DCGLW for the surface soil of Kori Unit-1 using RESRAD-ONSITE.