Until 1998, the majority of the site was worked for sand and gravel extraction. The resulting excavations were then partially or completely filled with pulverised fuel ash (PFA) and colliery spoil from the Selby coalfield. However, controlled landfill operations were seen as the only viable way of restoring the entire site to an attractive public amenity.
WRG began landfilling at Welbeck in 1998, following the granting of planning permission and a Waste Management Licence (now known as an Environmental Permit) in 1997.