The impact of volcanic ash fallout on industrial facilities: Natural-technological hazards in wastewater treatments (Grit removals)

Natural disasters are able to cause significant damage to chemical plants, structure, infrastructure and lifelines (power plants, fuel storage facilities, water treatment plants, etc.). Failures in these systems could worsen the effects on people, environment and economy due to natural disasters. In the literature such scenarios are known as Natural-Technological (Na-Tech) events; in this frame volcanic eruptions can trigger a wide range of Na-Tech hazards for both human health and environment. This chapter extends a recent study related to the analysis of the potential damage of primary (mechanical) treatments included in wastewater plants due to the fallout of volcanic ash produced by volcanic explosive eruptions. The work aims at the identification of the conditions leading to the functionality reduction of grit removal facilities. An application of the proposed approach to a case study, which is the surrounding Mt. Etna (Italy), is also given