G S Littlejohn, BSc, PhD, MICE, MIStructE, FGS. This paper was first published in GE’s March 1979 edition.
More than 70000 old mine workings have been charted in Britain, but at least another 30000 unrecorded workings exist as legislation making it compulsory to keep plans of old workings and shafts was not introduced until 1872. These workings are largely the product of coal mining operations in the 17th, 18th and 19th Centuries, when coal pillars were left to support the overlying strata. It is important to recognise that old workings due to the mining of silver, lead, shale and salt also exist, and at the outset of the Industrial Revolution iron minerals and refractory clays were extensively mined. The following text, however, concentrates on the major problems related to coal mining.