Modern Methodologies of Risk Assessment for Contaminated Sites Applied to an Industrial Accident Occurred in 1976

In this study modern methodologies of risk analysis were applied to establish the consequences of an industrial accident occurred more than 30 years ago. On September 26, 1976 in the Enichem (formerly ANIC) plant for ammonia production located in Manfredonia (Foggia, Italy) the column for the treatment of synthesis gas feed broken off. As consequence of the column collapse, the substances present in the process, i.e. arsenic compounds, and the column filler materials came out forming a puff which fell to the ground on a large area. Promptly and during some months after the accident, remediation operations were carried out in order to remove the soil contamination by arsenic compounds. The authors applied the approaches for risk assessment of contaminated sites, currently adopted at international level, with the aim of evaluate the effectiveness of remediation operations and the human health risk of the workers in the plant.