Environmental impact assessment of radioactive water pipe leakage at NPP Paks

Abstract

Environmental impact of the leakage of radioactive water into the soil from a subsurface-pipeline on the site of NPP Paks was studied to assess the size of the contaminated area and to estimate the potential migration of radioisotopes. For this aim a comprehensive analysis study was performed on soil samples taken from the contaminated area. The activity concentration of representative radionuclides (such as ¹³⁷Cs, ¹³⁴Cs, ⁶⁰Co, ⁵⁴Mn, ⁷Be, ³H and ⁹⁰Sr), the composition of soil, the distribution of radioactivity in different grain size fractions and the pH of soil were determined. Dissolving experiments with synthetic acidic rain water was also carried out. Results of the activity-measurements show that the average activity concentrations in the case of all isotopes are below the exemption limit given by the authority. The short-term migration of radioisotopes has been found to be negligible. Since pH of the soil is about natural and the radionuclides are very strongly bounded to the soil, the risk of the long-scale groundwater contamination is low.