Cengio and Saliceto

Our remediation project at the former Acna site has given new life to the Bormida Valley.

The regeneration of a century-old production plant

The Cengio and Saliceto Site of National Priority is located in the Bormida river valley, in the province of Savona, and covers an area of approximately 67 hectares. Its origin dates back to 1882, when a small dynamite factory was built for the production of explosives. In 1925, it was converted by Acna, short for Aziende Chimiche Nazionali Associate, into a factory for producing intermediates for dyes and pharmaceuticals. In 1931, it was taken over by the Montecatini company and then by Montedison in 1964. In 1988, after a century of operation by companies outside the Eni group, Acna merged with Enimont as part of the industrial rescue operations ordered by the Italian government. In 1991 the plant was transferred to Enichem, now Eni Rewind, which permanently stopped production in 1999. The remediation plan began in 1988 and was relaunched in 2000 with the signing of a Programme Deal between Acna, the Ministries of the Environment, Industry and Health, the Regions of Liguria and Piedmont and the Government Delegate Commissioner. As of 31 December 2020, Eni Rewind has spent over €360 million on the site's environmental remediation and estimates to incur further costs of approximately €40 million. This is a significant spending commitment that far exceeds the 300 billion lire forecast in the Programme Deal.

Our activities in Cengio and Saliceto

The remediation of the site began in 1988, following a decision by the Council of Ministers who recognised Val Bormida to be an "area at high risk of environmental crisis". The first containment works, including alternating masonry, concrete, plastic diaphragms, jet grouting and drainage trenches, were carried out in 1984 to prevent groundwater from seeping from the site to external areas. A cement-bentonite plastic diaphragm was later placed in the impermeable marly substrate, interposed with HDPE. The Programme Agreement signed in 2000 divided the area into four homogeneous zones for permanent safety measures and remediation works: Zone A1 is the area designated for the storage of materials from the other zones; Zone A2 is the plant area where the Torrione, the symbol of Cengio, is located; Zone A3 is the wetland area; and Zone A4, known as Pian Rocchetta, which is located in a bend on the right bank of the Bormida river, about one kilometre from the industrial site. The Delegated Government Commissioner approved a specific remediation project for each area in 2006. We have already completed work and obtained the relevant remediation certificates for Zones A2 and A4, so these areas are now available for new development and regeneration projects.