SUBSEA SERVICES

ECOTERRES team wins contract to treat contaminated spoil

18 years ago

The Walloon Minister of Port Infrastructure in Belgium has confirmed that, following a European tender, a contract has been awarded to Ecoterres SA for the treatment of 285,000 m³ of contaminated silt per annum from waterways in the Walloon region over a four year period.

In the treatment process to be used, contaminated particles in dredged material will be permanently immobilised. Though the pollutants will remain present in the sludge, they will be entirely neutralised by the process of encapsulation.

Due to environmental legislation in Wallonia which definines any silt dredged from waterways as waste, no maintenance dredging had been performed since the early 1990s. As a result, some 2.1 million m3 of accumulated silt is now a hindrance for navigation in Walloon waterways. Priority maintenance dredging contracts will be put out to tender this year.

A consortium led by DEME Group subsidiary Ecoterres, which also includes Envirowall and Ferrari, was recently awarded a contract for management of Category B dredging spoil. The value of the contract is some ¢16.37m per annum.

Walloon regulations classify dredging spoil into two categories. Non-polluted sludge is in Category A and polluted sludge is in Category B.

For the actual processing of the dredging spoil, Ecoterres will be employing a new solution developed in partnership with the Port of Charleroi and the Walloon environmental agency, SPAQUE, through SEDISOL.

The fixed processing installation will be built in Farciennes along the river Sambre, and will form the heart of a centre for managing sludge, to be known s Sedipôle. SEDISOL SA has all the necessary permits in place and construction of the new installation should get under way shortly. It should be operational in autumn 2009. The Solvay Novosol process will be used to treat the sludge. The new Sedisol facility will be operated by the Ecoterres led consortium.