Restoration sites

Four former mineral extraction sites in Wales were treated with PAS100 compost and biofertiliser derived from anaerobic digestate to assess the impact on the establishment of vegetation – thereby helping to reduce erosion in high rainfall areas.

The sites varied in use but shared a need for restoration. At Ffos-y-fran Land Reclamation Scheme – an open cast mine operation near Merthyr Tydfil – field trials were held on an overburden tip. Borras Airfield Quarry is an active sand and gravel quarry with areas waiting to be restored; while trials at Oakley Quarry at Blaenau Ffestiniog took place on an overburden and waste slate tip. The final site was located at Bryn Posteg on a partially restored section of domestic landfill.

 The project incorporated the use of both PAS 100 compost and biofertiliser and concluded that a single application of biofertiliser would have a more subtle improvement on vegetation growth beyond that enabled by compost addition. Anaerobic digestate could, therefore, offer a valuable benefit to growth, although further exploration is needed to provide conclusive evidence.