PRACHIN BURI: The Office of Atoms for Peace (OAP) yesterday said the hazardous caesium-137 contamination found at a metal factory in Prachin Buri's Kabin Buri district has been safely contained.
Kitkawin Aramrun, OAP senior radiation physicist, confirmed yesterday at the provincial government complex that he found caesium-137-contaminated furnace dust at a local steel plant. There was no contamination detected within a 5km radius around the factory, he said.
Regarding the furnace dust, he said the "contaminated furnace dust was contained within the compound", adding "there is no contamination in the environment in Prachin Buri".
Many bags of furnace dust from the plant were removed from the premises, but officials did not find caesium-137 contamination among them, he said, adding the plant's 70 employees were also cleared.
The announcement by the OAP and Prachin Buri provincial officials followed the disappearance of a large tube of caesium-137 from a National Power Plant 5A Company facility in the 304 Industrial Park in tambon Tha Tum of Si Maha Phot district.
Its disappearance was reported to the police on March 10. Radioactive caesium-137 is used in measuring devices.
The missing metal tube is about 13cm in diameter and 20cm in length and weighs 25kg. It has still not been found. Officials suspect it was stolen and sold as scrap metal.
Officials said on Sunday that the discovery of the contamination prompted the sealing of the steel plant in tambon Hat Nang Kaeo.
Authorities yesterday still refused to name the steel plant, saying only that it was about 10km away from a power station.
OAP secretary-general Permsuk Sutchaphiwat said the plant melted scrap metal at 1,000C, and melted metal does not get contaminated.
Caesium-137 naturally leaves metal as it melts at 600C and it can only be found in furnace dust, he said, adding furnace dust is kept inside a closed system.
Mr Permsuk said management used one big bag of the contaminated furnace dust as ground-fill inside its compound. The OAP had contaminated soil excavated and safely stored inside the plant warehouse, he said.
The melting plant was closed and cordoned off, he said, adding the OAP will find a safe place to dispose of the contaminated furnace dust.
Provincial governor Narong Nakhonchinda said there were 10 big bags of contaminated furnace dust, each weighing about 1 tonne.
Provincial health chief Dr Surin Suebsueng said caesium-137 contamination could harm skin, the digestive and nervous systems and cause leukaemia.
Symptoms include seizure, vomiting and diarrhoea, he said, noting no patient in the area has shown such symptoms.