The Bussac cement factory, situated in the Nouvelle-Aquitaine region, has been in operation since 1976. It supplies the south-western corner of France and, in 2016, produced 604,000 tonnes of cement.
The limestone quarry operates across a surface area of 190 ha and has a 30-year authorisation lasting until 2036. It is authorised for an average annual production of 1.4 million tonnes of limestone and marlstone. It will be restructured as body of water surrounded by a prairie.
The limestone quarry is situated in a wooded environment, comprising a vast siliceous region of which the Landes de Gascogne forms the main part. It is located at the heart of an area recognised for its ecological interest (Natural zones of ecological interest ZNIEFF I and II, Natura 2000 site "LANDES DE MONTENDRE").
As part of the redevelopment and expansion of the quarry in 2006, Ciments Calcia acquired four plots of land in order to implement ecological restoration and management measures to compensate for the potential impact associated with this expansion. These four compensatory sites of exceptional ecological interest, "Terrier Chauvrau", "Ardillasses", "Terrier Pelet" and "Nauves plates", cover an area of approximately 100 ha. The management and ecological monitoring of these areas has been entrusted to the "Conservatoire d'Espaces naturels de Poitou Charentes".
The limestone quarry consists of prairies, heath and afforestation areas as well as a large operational platform.
Several protected and threatened plant species have been recorded on site, including the round-leaved sundew and the spoonleaf sundew (Drosera intermedia and Drosera rotundiolia), the common hedgehyssop (Gratiole officinale), northern bedstraw (Galium boreale), bog myrtle (Myrica gale), hogs fennel (Peucedanum officinale).
The site is also host to the European pond turtle, Emys orbicularis, a protected species of turtle.
Biodiversity on compensatory site:
The compensatory sites are characterised by an exceptional diversity of plants and interconnected environments.
Between the two sites of Chauvrau and Terrier Pelet, 37 separated habitats and 303 plant species have been recorded. They also host several native species, such as the marbled newt (Triturus marmoratus), the false ringlet (Coenonympha oedippus), the European pond turtle (Emys orbicularis), etc.
These sites also provide a home for two plant species which have spread from the quarry, hogs fennel (Peucedanum officinale) and the common hedgehyssop (Gratiola officinalis).
Ardillasses: this site also comprises a mesh of ponds, prairies, afforestation, moors and peat bog with sphagnum mosses. Several species of national interest have been recorded on site: Drosera intermedia, Drosera rotundifolia, Gratiola officinalis, Kickxia cirrhosa, Pilularia globulifera.
The compensatory site at Nauves Plates is mainly covered with heaths growing under the canopy of pine trees, with some ponds and wet moorland. Drosera intermedia is located on this site.
Ongoing nature projects:
The initiatives being carried out at the quarry and compensatory sites are as follows:
- At the quarry, the following actions were performed: transplanting and sowing Peucédan officinale to ensure the recolonisation of the quarry areas, discussions regarding the establishment of a Peregrine falcon nesting box and the creation of reptile shelters.
- Within the compensatory sites, the objective is to ensure the long-term sustainability of the innovation sites which are of great ecological interest. In order to achieve this, measures consist of carrying out ecological rehabilitation works and management of the areas under threat. Each compensatory site has a management plan in place and is subject to ecological monitoring.
- Acquisition of new compensatory plots as part of the ecological management programme.
Finally, the quarry has adopted an SMbio biodiversity management system, which is recognised as part of the National Biodiversity Strategy. It includes identifying challenges to biodiversity, the implementation of an action plan and the regular monitoring of the measures carried out on site.