Cefn Mawr is a limestone quarry located west of Mold in North Wales, between the villages of Pant-y-buarth and Cadole. The majority of the extracted limestone supplies the cement making process at Hanson Cement, Padeswood, Mold, which in turn supplies the building and development sector. The Hanson landholding around the quarry is designated as a SSSI ( Site of Special Scientific Interest) and SAC ( Special Areas of Conservation) and named the Alyn Valley Woods and Alyn Gorge Caves SSSI/SAC. Hanson manage this land to promote biodiversity and have a biodiversity action plan in place as well as a detailed site management plan to maintain and enhance the habitats.
The site is undergoing progressive restoration which will return the site to calcareous grassland, scrub and woodland. Techniques including translocation of soil and plant material from previously restored benches and on site plant nurseries together with natural regeneration as well as planting will be employed.
Extraction activities have led to the formation of artificial features within the quarry that mimic those found in the natural landscape, such as rocky coastal cliffs, upland scree slopes and limestone pavement. Broadleaved woodland, species-rich calcareous grassland and ponds are present, all of which are UKBAP priority habitats.
Statutorily-protected species (e.g. bats and badgers) are found on the site and some species present are listed on the UK, Flintshire and Denbighshire BAPs (e.g. Fritillaries). Nationally scarce plants such as Green-flowered Helleborine, Spring Sandwort and Stinking Hellebore are also present.
Habitats are monitored annually by an ecological consultant, ensuring conditions remain favourable for many species. Management work is adjusted accordingly.
Limestone grassland is an important eco-system forming part of the SSSI/SAC designated area. It has a highly diverse flora with different species of orchids being recorded here. The flora gives rise to populations of important insect groups, most notably butterflies. An annual survey of butterflies on and around the grassland has discovered 27 species feeding and laying eggs on a range of flora, several of the butterflies being UK/local BAP species themselves. Other insects such as bee-flies and Yellow meadow-ants also exist.
Successful maintenance of the grassland has involved reducing scrub and bracken, whilst introducing a grazing regime in consultation with National Resources Wales (NRW).