Assessing and monitoring the potential impacts of dewatering at the largest quarry in Wales

Cornelly Quarry Groundwater Assessments

Cornelly Quarry provides over one million tonnes of limestone per year, primarily for the steel mill at Port Talbot. We have provided environmental services for quarry operations at the site for many years, including environmental data collection and review, environmental statements, and Review of Old Mineral Permissions (ROMP) submissions.

We have assessed the potential impacts of quarry dewatering on the level of the water table and other receptors as well as the hydrogeology of the nearby Kenfig sand dunes, which are designated under the Habitats Directive.

We developed a groundwater model, based on our conceptual model. This was an iterative process with calibration against the extensive baseline dataset of groundwater levels and flows (much of it collected by ourselves). Data continues to be collected from over 100 local monitoring locations, representing the most extensive hydrometric dataset around any quarry in the UK.

The deepest quarry in this area of South Wales, Tarmac proposes to deepen it further over the coming decades. We will continue to review and assess monitoring data to confirm predicted impacts and identify mitigation where appropriate.