Radon and uranium content distribution in groundwater of the Eorae mountain area, Chungju, Korea

Eorae mountain which is located in the Ogcheon metamorphic zone, was reported high radioactivity rock character. Therefore, 68 groundwaters around Eorae mountain area were sampled according to the geological radioactivity data and radioactive element such as uranium and radon (222Rn) were analyzed to understand radioactive element distribution. U and 222Rn contents distribution was different around Gongju fault line. The U content ranged from < 0.07 to 84.7 μg/L and 222Rn content ranged from 1.01 to 428 Bq/L. The average U and 222Rn content of northern and eastern part were high, which place was close to Eorae mountain.