​​​​​​​​​​​​​​​​​​​Tellus involves two types of surveying – airborne geophysical surveying using a low-flying aircraft and ground-based geochemical surveying of soil, stream water and stream sediment.

During 2021 the Tellus Survey aircraft flew in County Cork and neighbouring parts of Limerick, Waterford and Tipperary. The survey finished in September 2021. The Tellus ground survey was underway across the Greater Dublin Area, following this sampling teams moved to South East Ireland.