Rehabilitation of a site in Cantal: a strong comeback of biodiversity
After decades of operation the Foufouilloux Nord site has been in the hands of nature and its biodiversity since 2014.
The quarry that we have been operating since 2005, near Murat in Cantal, provides diatomaceous earth, which is highly sought after for its filtration properties. Today, the 30-hectare northern site is home to a wetland, which will become a showcase for the region's biodiversity, a perfect illustration of our proactive approach to minimising our environmental impact. Overview of the ecological rehabilitation of a site that reconnects with an entire ecosystem.
Diatomite, formed by the accumulation of fossilised micro-algae, is known for its filtering properties, which makes it a highly sought-after mineral since there are only two sites in Europe likely, due to the quality of their deposits, to supply the food and pharmaceutical markets. A real geological treasure of the Cantal, the site located near Murat is now recognised as a site of national interest. Diatomite or diatomaceous earth is used in many everyday products and its filtering and purifying properties are unequalled to this day.
A source with strategic goals
The diatomite extracted from the Foufouilloux site constitutes the raw material for our processing plant in Murat (46 employees) located 5 km from the quarry, which produces 20,000 tonnes of diatomaceous earth per year divided into 16 product references.
World production in 2019 was 1.8 million tonnes. France is the second largest producer in the world behind the United States with an annual tonnage of between 200,000 and 250,000 tonnes. The most common applications are water filtration and wine and beer filtration. In the pharmaceutical industry, diatomite-based filter materials are also used for filtration and purification by active ingredient (antibiotics, vitamin products, glucose bags). In medicine, they can also be used for the filtration of human blood plasma. Diatomite is used as a support for paints, absorbs oils and fats, is used for cleaning soils and in agronomy (amendment of certain soils) among others. All these uses require products of high specificity and high purity, with high added value.
From operation to rehabilitation
Since 2014, as the northern area of the site has been extracted, rehabilitation works have replaced quarrying operations. Under the leadership of a quadripartite commission (State, local authorities, associations for the environment and industrialists), an entire engineering reconstruction of the site and its biodiversity was developed and implemented. Among several projects, the commission's preferred option was to return to grassland that could be mowed and grazed once the quarry was filled in, and to create a 3-hectare wetland.
The approach is simple: to base the project on a natural evolutionary process and to favour the aquatic environment. The area thus includes a semi-deep water zone, a swamp suitable for the habitat of recovered flora and fauna, and a seasonal flood zone. Access roads or "waterways" have been recreated to facilitate animal movement. Hedges have been planted to accommodate birdlife; scree slopes allow reptiles, insects and other hedgehogs to return. In two years, the grazing area has been restored to the original quality of soil suitable for agriculture. The project won the Imerys Sustainable Development Challenge in 2021, out of 334 projects.
A reborn ecosystem
In just a few years, our teams in Murat, assisted by independent ecologists, have been able to observe the incredible resilience of nature. Many species that had deserted the site are returning: lapwings, grebes and curlews, for example. Otters have taken over the aquatic area and the flora has returned: the bladderwort, a carnivorous plant that grows in fresh water, is once again part of the landscape.
These few examples are listed with many others in a biodiversity inventory monitored by ecologists and aimed at collecting all the species returning to the Murat site. Numerous ecological rehabilitation actions have gone as far as the creation of a "blue corridor" by modifying watercourses such as the La Gaselle stream to restore its original biodiversity. Within the framework of Natura 2000, these initiatives provide the best conditions to make the oldest part of our site a favourable place for amphibians, invertebrates and birds, all species typical of wetlands.
A project that goes beyond the site
The rehabilitation of Foufouilloux Nord is a perfect illustration of our commitments - and of our objectives as defined in the SustainAgility ™ programme. Our ultimate objective is to avoid any loss of biodiversity, a commitment made through our partnership with "act4nature, companies for biodiversity", effective collaboration in France and throughout the world. The rehabilitation of the site was designed to restore the ecosystem and local activities, particularly agricultural and even tourist activities.
Our team in Murat aims to restore the white-clawed crayfish's habitat to allow it to return to populate this area, which it had deserted. As part of a continuous improvement approach, all our employees in Murat have taken part in the project; those who integrate the site are particularly involved in this approach and all of them support the project to create green corridors in order to enrich the local fauna and flora. Collaboration with local primary and secondary schools is being considered in order to raise awareness and to develop new solutions in relation to the future rehabilitation of the South site. The general state of mind? To think "environmental excellence" continuously, to reduce the impact of activities as soon as possible and above all to foster "this state of mind which I encourage because we all relate to it on the site. Watching nature regain its rights, seeing a flight of lapwings go by, is to me a true experience of ecology," says François Gueidan, the site's director and the first enthusiastic observer of this ecological revival.
Diatomaceous earth – Facts & Figures
Did you know?
- The Murat site produces 20,000 tonnes of diatomaceous earth per year, from 60,000 tonnes of ores extracted.
- 150 grams of diatomaceous earth can filter 100 litres of liquid.
- 4.8 billion litres of European beer is filtered with the site's diatomaceous earth per year.
- 120 million litres of fruit juice is filtered with the site's diatomaceous earth per year.
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