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information and results of specific Research & development
quotation in order to determine
TABLE 1 Concentration of contaminant determined in samples reliable costs of:
• Characterisation,(characterisation
of sediment to be dredged (option 1: 22,000 m3; option
2: 12,400 m3), different level of contamination (“green” plan, sampling, analysis and
or “yellow” sediments), and possible presence of about data elaboration);
50% in volume of biomass buried below the sandy • Dredging (mob de-mob,turbidity
seabed [16, 17]; Figure 8. curtains, monitoring and after-
Subsequently, four management scenarios based on dredging analysis);
beneficial reuse of sediments were predicted; all of them • Transport (capacity load of
exclude landfill disposal.For each management scenario, trucks, daily rent of vehicles
a cost-benefit analysis was prepared,considering several and number of trips);
• On-shoredeposit(preparation,
impermeabilisation);
• Treatment (soil washing, land
farming);
• Other costs (safety, taxes and
unexpected costs).
So, the following scenarios were
identified in order to have an
economic,social and environmental
advantage (Figure 8). They can be
briefly described as follows:
A - Sport Facilities: execution of
an area dedicated to sports
activities, such as beach volley
and/or beach soccer;
B - Coastal restoration:accommodation
of sediments at the cliff’s foot
along 110 m of back shore;
C - Harbour layout: building of a
Confined Disposal Facilities
(CDF) in order to spill over
the dredged contaminated
sediments and enlarge the
current Harbour layout;
D - Sediment sale: sale of dredged
sediments to proper industrial sectors.

Discussion

Dredging within Favignana’s Harbour is periodically
needed to ensure the safety of navigation and an
adequate depth through time. With the present layout,
the entrance to the harbour is often compromised by

43EAI Energia, Ambiente e Innovazione 4/2015