South Gloucestershire Mines Research Group

From the website:

“The South Gloucestershire Mines Research Group (SGMRG) was set up by local people to understand, record and, where appropriate, preserve the remains of what was once an extensive industry for the present community and future generations. SGMRG is a voluntary organisation that relies on grants and donations from local people. Our membership is made up of archaeologists, surveyors, historians, engineers, cavers and those simply interested in finding more about what lies under their feet. We have regular meetings, walks and talks, including the opportunity to get involved in exploration, archaeology and restoration work.”

Details of events, membership, publications and other resources are on their website.