INR and CNCAN experience in remediation of norm contaminated sites - A case study

In 2006, the National Commission for Nuclear Activities Control was notified by the mayor of a commune, claiming a radioactive contamination of the soil, due to some past discharges of waste waters resulted from the exploitation of natural gases in the area, ceased for several years now . After the radiological investigation of the area, CNCAN confirmed the radioactive contamination of the soil with Naturally Occurring Radioactive Materials (NORM). The polluter was identified and asked to take all the necessary actions to remedy the contaminated area. The contaminated site was fenced and warning signs have been posted. In order to assess the level of radioactive contamination, a study was performed, in two different stages. Both studies were contracted by the Radiation Protection Laboratory of Pitesti Nuclear Research Branch, which is approved by CNCAN to perform radioactivity measurements of environmental samples. The results of the ambient dose rates mapping and laboratory gamma-spectrometry analyses of surface water, spontaneous vegetation and soil samples were used to estimate the quantity of the contaminated soil and the doses to population, due to the presence of NORM waste into the environment. Based on this information, several solutions for the remediation of the contaminated area were proposed and discussed. Waiting for the meteorological conditions to allow the removal of the contaminated soil from the site, an intermediate solution for the storage of this soil was decided. The solution proposed for the disposal of the contaminated soil was also discussed, but further consultation with the environmental protection authorities is still needed. (authors)