Discovered radioactive source in a railway wagon, loaded with scrap metal in Stomana Industry” S.A.

Site with SIR or place of the event: “Stomana Industry” S.A, Pernik

Event description:

The NRA emergency centre was notified that on 5^th March 2010 the portal radiation monitoring system of the “Stomana Industry” S.A., Pernik detected elevated radiation level in a scrap loaded railway wagon. The railway wagon has been stationed on a separate track on a special platform on site and has been put under surveillance.
The detailed measurements have shown slightly elevated radiation levels, up to 0,33 µSv/h, on the surface of a small area on the side of the wagon. As a reference, the values of the natural gamma background in the area of Pernik are between 0,07 and 0,11 µSv/h. Following a field spectrometric analysis, the presence of the radioactive isotope Ra-226 (radium-226) has been identified.

On the same day the wagon has been partly unloaded. The detail, causing the elevated radiation levels, has been discovered and removed from the scrap. The later represented deformed control devise weighting about 200 g. The measured values of the gamma dose rate at 1 m have been up to 0.15 µSv/h and in contact on the surface – up to 5.1 µSv/h.

After additional measurements the wagon has been released for unloading. The source has been packed and put in a safe place for temporary safe storage, and latter will be disposed as radioactive waste by the State Enterprise “Radioactive Waste”.