Makes sense to extract the coal if the ground is collapsing from shallow workings,
But strange ,they did nt think of this before building around this site,some of them buildings must be built on top of the same workings.
nothing particularly unusual about well-known problems being glossed over or disregarded under then-current planning regulations.
Docklands Light Railway had a long pre-construction phase of reinforcement of historic culverts and underground structures, as did Jubilee Line Extension - and these are in central London. London Eye was used as a vehicle for carrying out reinforcement works to the Northern and Bakerloo Lines which had originally been designed in the 1970s ( the Bakerloo Line having been reinforced with hoops allegedly taken from U-boat hulls, as long ago as the 1920s ).
The Brunel Tunnel under the Thames was re-lined in the mid-90s to deal with severe water ingress and structural deterioration that had been under study since the 1960s, but it took the Canary Wharf development to push it onto centre stage, and the Waterloo International Terminal ( built in 1992-3 ) meant that the Waterloo and City Line tunnels at Waterloo required remedial works to "temporary" works originally done following a bomb strike during the Blitz.
''the stopes soared beyond the range of our caplamps' - David Bick...... How times change .... oh, I don't know, I've still got a lamp like that.