The scene only takes place a few times a year. On the road along the Meurthe last week, trucks were lined up in single file waiting for their turn to load their cargo of salt. On their GPS, a starting point, the last salt mine in France in Varangéville (Meurthe-et-Moselle). A place of arrival, among the hundreds of towns in France, north of the Loire, in the area which depends on this unique source of salt to cover the roads in winter. The cold spell, the snow and ice alert launched by Météo France herald the start of the season for the mine belonging to the Salins group, which since 2012 has brought together the saltworks of the South and the saltworks of the East.
Up to 600 trucks per day
Opened in 1856 on one of the largest underground salt deposits in France, the mine provides what we call rock salt, which comes from the bowels of the earth in the form of crushed rock, which is opposed to sea salt, obtained by evaporation. At a depth of 160 meters, it is in Varangéville that the last underground miners in France work – in what is also the last active mine in mainland France. Around thirty people take turns to meet the very seasonal demand. “Everything is prepared underground, explains Stéphane Bel, mine operations director. We take out blocks that can weigh up to a ton, then machines crush them. Then, we will have screens which will standardize the sizes, since for snow road salt, there is an NF standard which applies. » The gray colored salt coming out of the mine is ready to be loaded. In the middle of the winter season, when the weather conditions are the harshest, the mine receives visits from 500 to 600 trucks per day. Suffice to say that the entire commune of Varangéville and more broadly the neighboring town of Saint-Nicolas-de-Port must deal with one of the main industrial activities in the sector. On average, 100,000 tonnes of salt come out of the mine each year, five to six times more during very harsh winters, which are becoming increasingly rare.
A seesaw market
The mine is suffering the consequences of climate change, with a market that is much less clear than 20 years ago. “Clearly, the market is really up and down, worries Stéphane Bel. The last big winter we had was 2010. Since then, certain years have created a slight jolt but nothing comparable to that year. » A change in demand which forces the Salins group to work on other options for using salt, in order to maintain activity and jobs on the site. While the research office works from the Aigues-Mortes site in the Camargue on new outlets – for the moment kept top secret – the Varangéville factory has already diversified with half of its production of igneous salt, coming from of the same rock but obtained by dissolution after addition of water. Whiter is purer than rock salt, it is used for industry, water treatment, softeners, but also licking blocks for ruminants in agriculture.
With a fairly early warning of winter at the end of November, the mine is getting into battle order. The quantities extracted make it possible to meet demand, even strong over a fortnight. An – improbable – snow episode lasting more than a month would begin to show the limits of the mine, even with the two teams of miners mobilized in 2x8s. The contract between the mine and the State imposes this responsiveness, through all of the Interregional Roads Directorates located north of Lyon. The south of France is supplied by the salt works of Camargue, with salt which more closely resembles that which is on our tables. “The crux of the matter in commercial matters for salt is transport. The product itself has little value, but it is not profitable to drive a 30-ton truck 800 kilometers to salt roads. » Proximity as a source of profitability, the best recipe for making an industrial activity non-relocatable. With a few snowfalls or a few ice alerts, the Varangéville mine therefore has beautiful winters ahead of it.
