FN Bosco Marengo Plant – Update as at 09/11/2020

09 November 2020

​In May 2020, Sogin launched investigation operations in the FN Bosco Marengo Plant to remove anthropic materials found within the so-called “clearance area” of the Site. 

The performance of said operations was authorised in December 2019 by the ISIN Control Authority and submitted for knowledge to the competent local authorities. 

The materials subject to clearance operations are solids of common anthropic nature, mainly constituted of plastic, iron, concrete, wood, oil casks, etc., which have been probably buried over the last decades during the operation of the FN Plant. 

Said materials, adequately arranged in big bags or metal casks to be protected from weather events, will be analysed and sent to a landfill; the soil removed during the excavation procedure will be redistributed in the area to constitute a walking surface. During the site inspection, a small portion of soil (weighing a few kilograms) with a slight radiometric anomaly emerged from the excavation works at a depth of 1.5 metres. Based on the tests conducted on a sample, said anomaly could be ascribable to the presence of the radionuclide Caesium-137. 

This discovery was promptly notified to ISIN Control Authority, ARPA Piemonte, and the Municipality of Bosco Marengo, and a press release was published on 12 June 2020. Therefore, the operations were suspended pending further investigations to assess the origin and scope of the concerned area. Said investigations were carried out in July 2020 together with ARPA Piemonte. According to the findings of that operation, the anomaly exclusively appears in the original area of its discovery. The Cs-137 concentrations detected around the concerned area are, in fact, comparable with the natural concentration o Cs-137 in the environment. 

The presence of Cs-137 can be ascribable to the Chernobyl fallout. It presumably massed in that specific area due to the burial of plants resulting from the maintenance of the green zones of the Site, which occurred after the Chernobyl event. This assumption is compatible with the Cs-137 radiological fallout values at ground detected in the Province of Alessandria after the Chernobyl event. Given the above, the activities carried out in the Plant are not related to the discovery of Cs-137. 

As for the complete decommissioning of the FN Bosco Marengo Plant, operations were halted in June 2019 for the presence of 11 casks of liquid waste, discovered during the performance of radioactive waste characterization procedures for subsequent treatment. Said 11 casks had been safely stored within the Bosco Marengo Site since the ‘90s, and they contained some radionuclides not covered by the Plant’s industrial operations. 

After the discovery, upon a request of the Control Authority, Sogin adopted measures and conducted due investigations that resulted in assessing the presence of the above radionuclides in the liquid waste contained in the 11 casks and excluding it in any other premises of the Plant, as well as other liquid and gasseous effluents of the Site. 

The ISIN Control Authority is currently carrying out the preliminary inquiries to resume decommissioning operations and carry out the treatment of liquid waste that will be sent and safely stored in the National Repository.