The application of so -called ‘steel snails’ – a residual product from Tata Steel – in construction projects leads to environmental damage in a large part of the cases. Although the use of steel snails is legal and frequent, especially in infastructure projects, the Human Environment and Transport Inspectorate (ILT) concludes that after its own research at ten locations Nine of it has caused environmental damage.
Because there has been no records where steel snails have been applied in the Netherlands, according to the ILT there is a high risk that steel snails have “caused or have started” at all kinds of locations in the Netherlands “. “Realizing locations is a lot like looking for a pin in a haystack.”
Steel snails are a stony material that is released during the production of steel. In the Netherlands it is applied as a replacement of sand in, for example, road construction, land retraction or bank reinforcements. In principle, this is a circular: a residual product is reused.
For a long time there have been indications that steel snails can lead to environmental damage in practice. When they come into contact with water, the acidity of the water drops and becomes comparable to sink extractor. As a result, ‘almost all conceivable heavy metals’ can be released from the snails, Thus the RIVM in 2023. This can lead to fish mortality and the death of water and soil life.
Ground increase
Moreover, the suspicion is that steel snails that have come into contact with water are the cause of complaints among local residents, such as bloody noses, burns and skin irritation. Well -known examples of locations where large -scale pollution arose his golf course The Dutch in the Betuwe and a location in Eerbeek where steel snails served as a ground lift. With the latter, local residents complained about health problems.
As early as 2023, the ILT warned that legislation on steel snails failed to prevent environmental risks. Now there is more insight into how often the problems occur. The inspection itself investigated ten locations, from Leeuwarden to Oude Tonge in South Holland, and found environmental problems in almost all places.
The ILT is still investigating fourteen other locations; There are suspicions of environmental damage with several of them. At two of the ten locations that the ILT already investigated, the steel snails have now been removed or ‘insulated’. In the Frisian Dokkum that happened once; A brand new road was completely redesigned for this. Only in this way could 7,000 tons of steel snails that were used as a foundation. Heavy metals leaked out.
Just like in 2023, the ILT now also questions the functioning of the market for steel snails. It is known that parties that purchase steel snails sometimes get money for this – instead of paying for the material themselves. “This gives an incentive to use more steel snails in a location than necessary,” wrote the ILT two years ago. The more steel snails you use, the greater the environmental risks. (Tata Steel does not bring the steel snails on the market itself, which runs through building material dealer Pelt & Hooykaas).
Even now, the ILT is again critical of the course of the trade in steel snails. According to the Service, the Netherlands also appears to import large amounts of steel snail, probably about as much as the annual production of Tata Steel. For a residual product that is striking. “The question here is why the Netherlands imports LD steel slag.” LD steel snails are the type of steel snails in question.
The registration of trade also falls short according to the ILT. For example, a load of steel snails that are known to the inspection does not appear to be found in ‘international data files’.
Open water
The ILT concludes that adjusting the ‘standard frame’ takes time. “Until then, new environmental risks and problems must be prevented.” However, the inspection itself can do little against that.
The ILT did not look at the use of steel snails in open water. Out Research at Wageningen University & Research It turned out earlier that the application of steel snails in moving water probably does not entail any risks. Nevertheless, last year Rijkswaterstaat decided to abandon the use of steel snails for sailing channel reinforcement in the Westerschelde. There was a lot of resistance to local authorities.