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

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

Event description:

During the entrance check of a scrap-loaded truck in “Stomana Industry” S.A. (town of Pernik) a source, containing Ra-226, representing control device with a luminous dial, has been discovered.

The NRA emergency centre was notified that on 28^th April 2010 the portal radiation monitoring system of the “Stomana Industry” S.A. – Pernik detected elevated radiation level in a scrap-loaded truck, supplied from the town of Samokov. The truck has been stationed on a special platform on site and has been put under surveillance.

The detailed measurements have shown elevated radiation levels, up to 2.1 µSv/h, on the surface of a small area on the top of the truck. 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.

The truck has been partly unloaded. The detail, causing the elevated radiation levels, has been discovered and removed from the scrap. The later represented control device with a luminous dial. The measured values of the gamma dose rate at 1 m have been up to 0.22 µSv/h and in contact – up to 5.2 µSv/h. Probably the isotope Ra-226 has been included as an ingredient of a luminous paint.

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”. After additional measurements the truck has been released for unloading.