Just over 100 miners worked during the nine years at Combe Down. Most were from the South Wales coalfields, with a small number from Yorkshire, the Forest of Dean and local limestone mines near Bath.
The miners were brought in for their specific skills and experience of working with timber and steel support structures, relevant to both coal and stone mining. Despite working in difficult and dangerous conditions, the miners appreciated the improved working conditions and lack of dust and dirt commonly found in coal mines. Welsh camaraderie was evident throughout the project, and connections and contact with the Combe Down community reinforced by the fact that many of the miners lodged in Combe Down or Bath during the week. Sound friendships and firm links were made, resulting in Hydrock workforce initiated events such as rugby matches against local players.