The project will investigate potential 'upgrades' in ecological restoration at mineral extraction sites, with a view to these being supplied as biodiversity offsets. These 'upgrades' would go beyond the requirements of agreed site restoration plans and good practice in the minerals industry for nature conservation.

Biodiversity offsetting is the delivery of measurable nature conservation outcomes as compensation for the unavoidable long-term impacts of development on habitats and species. It requires an effective metric (measurement method) to calculate the amount of biodiversity present at development sites as well the amount of biodiversity resulting from offset activities. Defra has issued a habitat-based metric for use by current voluntary biodiversity offset pilot projects in England. Somerset County Council has published an alternative species-based approach to derive biodiversity units for offsets.

Ecological restoration activities at mineral extraction sites have a number of strengths when seeking to ensure an adequate supply of offsets. For instance, site restoration plan activities are often large, making tangible contributions to biodiversity targets. They are planned with a long-term view of achieving net gain for biodiversity.

The objectives of our project are to identify examples of specific ecological restoration actions at mineral extraction sites that might achieve significant additional biodiversity gains which could be provided to others as offsets; to assess the suitability of current biodiversity offset metrics to measure the amount of biodiversity associated with the above actions make recommendations for the use of biodiversity offset metrics at mineral extraction sites. This includes any supplementary assessment techniques required.