Passing the salt

Now, anyone who has ever heard of Pinoso will know it is famed for wine (Pinoso’s bodega is the biggest producer of organic wine in the province), marble (we have the largest marble quarry in Europe), shoemaking (now largely a thing of the past), and Mediterranean agricultural products (Frutos Secos Mañán is one of the largest almond producers and processors in Europe). Not much is said about salt. Yet Pinoso is a major salt producer. Unfortunately, the town sees little of that wealth: the salt deposit is owned by the Spanish Treasury (Hacienda), and the profits from working it go to a French company within the Salins Group.

We’re friendly with wine. Well, we’re members of the local "Amigos del Vino" here in Pinoso. We usually go on trips out in a charabanc which have some passing association with wine. If possible, we like to drink some. But last week we went on a trip with a different focus. We followed the route of that salt from deep inside our emblematic hill down to the coast at La Mata and Torrevieja.

El Cabezo de la Sal—that rounded hill with the mobile phone masts on top—is a bit of a symbol to Pinoseros. It’s why the local Facebook page is called El Cabeço (Valencian spelling). It’s rounded because it’s a salt dome. The light salt mineral, halite, behaves plastically under pressure and, over millions of years, has pushed up through the surrounding rock like a giant volcanic salt mushroom (without the fire and brimstone), with roots thousands of metres below the surface. For generations, salt was won here the hard way. Miners ventured underground through shafts and workings, blasting and digging at the solid rock face and hauling blocks of halite out. If you’ve ever gone up there to La Cueva del Gigante, that too is an old, historical salt mine.

Everything changed around 1970, when traditional mining gave way to a far cleverer piece of engineering known as solution mining. Instead of sending men underground, deep boreholes were drilled well over a kilometre straight down into the salt dome. Water, drawn from nearby underground sources, is pumped down under pressure to dissolve the solid rock salt, turning it into heavy brine. To stop this dissolved cavity from eating upwards into the upper rock layers, engineers inject a floating layer of gasoil directly above the water inside the cavern. Acting as a protective blanket, the floating oil prevents fresh water from dissolving salt at the roof of the cavity and keeps the dissolution where it is wanted.

Hundreds of metres below ground, the extraction process creates gargantuan water-filled caverns. You might wonder if removing millions of tonnes of salt leaves precarious hollow voids. In truth, rock salt under extreme pressure behaves plastically, slowly deforming inward over time. The caverns are eventually abandoned when they reach their maximum size, the gasoil is removed and the water is allowed to escape. The salt then gradually closes the cavity naturally through a process known as halokinesis.

Once brine is pumped up to the surface, it rests in settling basins. The raw brine contains fine clay and mineral particles from deep inside the diapir (that’s why one of the local wines is called Diapiro, the same word in its Spanish form), and letting the liquid settle allows these impurities to sink to the bottom. What remains is a hyper-saline liquid far denser than normal water, perfectly prepared for a trip to the coast.

From Pinoso, the brine embarks on a cross-country trek along a pipeline over fifty kilometres long, stretching to the Mediterranean coast. Because Pinoso sits several hundred metres above sea level, gravity does much of the work. The pipeline drops by more than 600 metres on its journey to Torre, but because there are some hills and valleys in the way the system needs a helping hand from pumping stations at various stages.

We started at El Puntal, just on the approaches to Algueña, far too early in the morning for my liking, where the groundwater used in the salt-extraction process is drawn from deep underground. From there we headed off for Torre. Our first stop was for breakfast. Educational visits are one thing but the breakfast imperative is another.

Appetites sated, it was on to La Mata where the salt water from Pinoso discharges first into the green waters of the lagoon in this Natural Park surrounded by blocks of flats and ribbons of cars along the N-332. The lagoon acts as a giant natural evaporation basin that contains both seawater and "our brine". The sun and Mediterranean breeze gradually evaporate the water, increasing its salinity until, when it has reached a specific level, it is transferred to the larger Torrevieja, la Rosa, lagoon.

At La Mata, as well as salty sea tales, we were told about things as diverse as fig tree boundary markers and eucalyptus trees as an anti-malarial measure.

After another fuel stop, lunch that is, (with cheap wine from Castilla-La Mancha), we went on to La Rosa to see how the Pinoso brine eventually ended up in the huge piles of white salt reflected in the often pink, but not always, lagoon. I think it would be true to say that very few residents, or visitors, in Torrevieja, would know that around 60% of the salt produced there comes from inland Pinoso. Adding Pinoso’s dense brine to the natural seawater supply helps the operation produce hundreds of thousands of tonnes of salt every year and increases its profitability.

That salt travels far beyond the Costa Blanca. Shiploads are exported across Northern Europe and North America to keep roads clear during harsh winters, while other quantities are supplied to the chemical industry and are also refined into water-softening products and table salt. Given that Pinoso provides such a large proportion of the raw material, local campaigners and civic leaders have lobbied for formal recognition on commercial packaging, pushing for negotiations to include the name Pinoso on labels. It’s not there yet.

El Cabezo de la Sal even caught the eye of national strategists more recently. Around 2011, the salt caverns were investigated as a possible site for a strategic petroleum reserve, as deep salt caverns make ideal, leak-proof storage vaults for millions of barrels of crude oil or oil products. Local opposition was strong, however, and the project was eventually rejected. Instead, in 2021, the Valencian regional government declared El Cabezo de la Sal a Monumento Natural, giving it official protection under regional environmental law to preserve its unique geological structure, biodiversity, and landscape. That landscape itself is surprisingly recent: stripped bare over centuries by overgrazing, firewood collection, and timber cutting for salt mining—and with extreme, salty soils making natural regrowth tough—the familiar pine cover was only replanted in the mid-twentieth century.

So the next time you notice our hill just give a thought to its burbling innards and how at least some of it will be off to Torrevieja very soon.