Supporting a planning application to develop a new silica sand quarry

Quarry Development Cheshire

Sibelco submitted a planning application in 2017 to develop a new silica sand quarry on greenfield land. However, there was concern that, despite proposed wet process operations (using dredging techniques with no dewatering), the development could cause a permanent decline in water levels in an adjacent local wildlife site lake used for recreational fishing.

Various calculations and a preliminary groundwater catchment analysis were undertaken by us to determine the possible change in catchment area to the lake resulting from the development. Following the initial findings, we applied groundwater modelling to evaluate the effects of the post-development situation (a new restored lake on the mineral extraction site) and compared this with the current conditions.

The calculations and groundwater modelling gave consistent results with the key findings including a 40% to 60% reduction in base flow to the lake and an average water levels reduction of five centimetres lower compared to current situation. This equated to a potential 1.8% reduction in surface water area of the lake. It was advised that the addition of a silt and clay barrier to the north and east of the proposed new lake would reduce the reduction in groundwater flow to the existing lake.

Based on this, an acceptable way forward was agreed on with the Environment Agency with suitable planning conditions proposed.