Abstract:In order to find out degree of radioactive pollution in soil environment of plant and its surroundings, field investigation and statistical analysis were conducted on activity concentrations of radionuclides of 238U, 232Th, 226Ra, and 40K in surface soil around the plant (0~0.3 m) and in soil of 0~0.3, 0.3~0.6 and 0.6~0.9 m of heavy contamination points to find out their distribution characteristics in soil. The descriptive statistical results show that 238U has the highest activity concentration of 5 860 Bq/kg point in R1, while the other three nuclides (232Th, 226Ra, 40K) have the highest value of 930, 1 420, 367 Bq/kg in point R2. On the basis of statistical results, potential ecological risk index method and exposure assessment model were used to evaluate the pollution degree and harm degree to human health. The results show that point R1 and point R2 were strong ecological risk, point R3 was moderate potential ecological risk, and the other points were slight ecological hazard. There is no carcinogenic risk for children and adults through respiratory channels, while there is a non-carcinogenic risk for children through oral ingestion. There is possible non-carcinogenic risk for adults at point S1 and non-carcinogenic risk for others.