“The exploitation of basements is no longer fashionable”

“The exploitation of basements is no longer fashionable”

“The exploitation of the basements is no longer fashionable”, observes Robert Colbach, geologist and head of studies at the state geological service. “Luxembourg has forgotten its mining past,” he laments. A mining past which in fact almost disappeared with the end of mining in the 1980s, which represented almost the entire sector.

But could the country have reinvented itself by exploiting other mineral resources? At a time when the energy and digital transition requires rare metals and minerals in quantity, the country is however deprived of them. Alongside iron ore, “Luxembourg is not rich in mineral resources”, explains Robert Colbach, who even specifies that “Luxembourg’s subsoil has no rare metals and minerals”.

In the past, lead or copper mines existed on the territory of the Grand Duchy, but the last ones closed in the post-war period. A deposit of antimony – a rare mineral – exists near Goesdorf, but the mine closed in 1938 and the vein “is certainly not huge”, explains the geologist. “There is no reason to think that the exploitation can be profitable.”

The number of careers in decline

Another resource exists however on the territory, and in quantity, that of building materials: sandstone, dolomite, slate, gypsum, gravel or sand. But this geological availability has not paved the way for increased exploitation. On the contrary, the number of quarries has fallen: from several hundred in the past, there are now only eleven in the country.

This poses a problem, in a country where new constructions are numerous: “Today, we are unable to meet the national demand for building materials”, observes Robert Colbach. A phenomenon amplified by the end of the blast furnaces, which discharged slag into the slag heaps, slag itself used for construction.

This created a vacuum in domestic production, which was not compensated by the opening of new quarries. However, according to the geologist, attempts to open new quarries in Luxembourg have taken place. But, for decades, this has not led to any opening, he laments. For a reason according to him: the environmental constraints imposed by the administration of the Ministry of the Environment.

Environmental constraints

“Nature is important,” he concedes. But the demand for materials leads to imports from abroad, sometimes over long distances. However, “polluting emissions due to transport are not negligible, perhaps greater than those which would be caused by quarries”, he judges.

One of the main players in the field in the sector, Carrières Feidt, recognizes that in our time, it is “very, very difficult” to obtain authorization to open a new quarry. Environmental constraints are of course in question, even if the company claims to have a “very good contact with the environment” and that it is not a question of “bad will” on the part of the administration.

Many other constraints come into play, according to him, including one in particular: the acquisition of land covering a potential quarry. On the one hand, they are very expensive in Luxembourg. And they can belong to different owners: “If you have fifty owners on a potential quarry, the exploitation is null and void from the start”.

Limited recycling

It is therefore much easier at present to resort to extensions of existing careers than to open new ones, according to Carrières Feidt. “We have fairly substantial extension projects on the right track, and we are going to obtain the authorizations”, assures the carrier.

Recycling remains another modern solution for supplying materials, but it has its limits. “The possibilities of recycling these materials are limited to 30%, the rest comes from the quarries”, assesses Robert Colbach. Careers Feidt also recognizes that recycling is a solution “up to a certain point”, which cannot provide “the quantities necessary to meet the demand in Luxembourg”.

Space mining, a “nonsense”

There remains the exploitation of space resources, presented by some as the future of the sector. Luxembourg has in the past positioned itself in favor of space mining. “Nonsense”, according to Robert Colbach. “We have this on Earth, in the first 300 meters deep,” explains the geologist. “Exploitation is much easier and, from an economic point of view, much cheaper on Earth than on the Moon or asteroids,” he says.

It is therefore a question of refocusing on what is available nearby, according to the geologist. “The government slowed down so much that the requests were abandoned,” he explains. Hence the need “for Luxembourg to do what it can for construction materials”.