British building materials group Tarmac has launched 'Biodiversity Net Gain Habitat Banks', marketing former and active quarry sites as tradeable ecosystem credits. The scheme allows developers to offset habitat loss elsewhere by purchasing credits from Tarmac-managed land. It capitalises on England's mandatory net-gain requirement, which came into force in February 2024 and obliges developers to deliver a 10% biodiversity uplift on every project. Critics question whether extractive industry land can deliver genuine ecological value or whether the model simply monetises existing obligations. Tarmac joins a growing number of landowners entering the biodiversity credit market, where prices and quality standards remain largely unregulated.