Environmental radiation and radioactivity in the vicinity of the Semipalatinsk Test Site

The International Atomic Energy Agency's Mission to Kazakhstan studied the present environmental contamination and the exposure risk from nuclear tests performed at the Semipalatinsk Test Site. On this mission, EML scientists collected in-situ gamma-ray spectra, measured external gamma dose rates, and collected soil samples. With the exception of plowshare areas and near ground zero, all the areas visited had external dose rates within typical environmental levels. Measurements within a 15 km radius of ground zero showed elevated levels of¹³⁷Cs,¹⁵²Eu, and⁶⁰Co. The dose rate within ≈1 km of ground zero ranged from 500 to 30000 nGy·h⁻¹.