A very stringent technical confrontation this morning about the new dredging regulations, also in regard to SIN’s (Sites of National Interest), gave a preview of the presentation held in the afternoon about new dredging technologies.
The new regulations will allow to evaluate polluted sites not just on the basis of chemical parameters but on the basis of complex and innovative assessments that determine the actual overall hazardousness and the possible reutilization of the dredged sediments, or their possible release in open waters if not contaminated and not reusable for the replenishment of beaches, construction or others on the base of their physical characteristic.
It will be possible to take some areas out of the SIN list by making the dredging procedure more simple. Also it will be possible to use storage places for mud and dredged water (so called sediment tanks) with lower permeability characteristics than used today.
The ordinance brings some intelligent simplifications also, and finally, allowing for the reuse of the dredged sediments. On the other hand the push for constant simplification/facilitation brings the risk of promoting conservation instead of innovation.
A paradoxical situation in face of the major breakthrough presented in the afternoon: the dredging technologies of the Limpidho system by Decomar, about which ECQUOLOGIA and Giga have been talking about for a while.
The new dredging system allows to diversify the dredged sediments right after the extraction from the waterbed and to reuse over 80% of the extracted material, rendered devoid of water, and thus accumulable until it loses its salinity (3-6 months) for materials destined for construction work or immediately shipped to destination for the recovery of beaches.
Not only, but in the moment of the operation in the excavation phase no turbidity in created, so that eventual pollutants don’t spread with devastating effects for the environment, i.e. as seen recently with the massive death count of clams in La Spezia.
The interest raised by the presentation of Davide Benedetti of Decomar and of Prof. Giuliano Gabbani of the University of Florence (CSO of Giga) was significant, as has happened in the past months in La Spezia, Ravenna and Taranto, because many port operators, instead of trying to justify the use of excavation grabs – that by nature mix water and sediments and spread turbid and/or polluted water – by trying to make them ecological, prefer to dedicate themselves to developing new systems that really tackle the problem.
A very clear stance was taken by the representatives of the Ministry, the Icram and the Ispra as they said that they “didn’t go out on a limb” but they will provide a way to operate well, as with today’s subsidies they can only fund the emergencies of the emergencies.
Prof. Gabbani welcomed the new dredging legislation that finally leaves no doubt on suspected preferences or ministry guidelines towards the exclusive use of grabs in dredging operations. Nowadays the market must be open to all the best technologies and must favor the reuse of dredged materials.
The Limpidho System can operate at any depth and by placing it on a ship it can operate during normal port activities, both commercial and touristic.
Another sector in which Limpidho brings a breakthrough is the replenishment of beaches, since it can separate the sands by size, and if a replenishment isn’t done with specific sands it will last as much as the time in between two tides.
Throughout the day more innovative activities were presented for the monitoring of many indicators to complete the dredging activities with control systems, showing how some of the persistent affirmations of the morning – that tried to undermine the innovative nature of the new legislation – are just an attempt to defend a dredging sector that in Italy insist on not investing in innovation, with only a few exceptions.
Interesting was the point of view of Luigi Righini of Hera who called for a breakthrough in port dredging, by moving from big dredgings every number of years to smaller and continuous dredgings, especially now that new technologies would allow for this new approach. Far too often to recuperate material from dredged sediments enormous sediment-washing or soil-washing plants have been designed, or machinery to wash slime and mud stowed in sediment tanks, that when once their work is done become materials to be remedied and disposed of.
Also for this reason there is the need for a mobilization from below that asks for the removal of the polluted sediments that plague mani Italian ports and hydroelectric reservoirs, and that the removal doesn’t cause damage at the moment of the dredging. It is necessary that the political world states clearly that remediation is not moving, but solving the problem, and lifts the fog from the many situations in which, in spite of the obvious damage, there is a reluctancy to take adequate measures.