I have often wondered whether historic mining activities had any affect upon the PCNs at EDI. I found the following article regarding an abandoned shale mine that was dug to a depth of 177ft in 1892 but was abandoned in 1894 due to "sand and gravel bursting through roof at crop".
https://www.scottishshale.co.uk/GazM...ton33Mine.html
The shaft was just north of the runway 24 threshhold and the workings went northwards under the River Almond so I would be surprised if they have any affect upon the current infrastracure at EDI. These ground conditions may however have been a significant factor in the feasibility and cost of EARL proposals and the mine workings may need to be taken into account if a second parallel runway is added at EDI in twenty or thirty years time.
There are many interesting maps on the NLS website that allow users to fade between various current and various historic maps using a slider labeled "Transparency". Here is an example for EDI;
Explore georeferenced maps - Map images - National Library of Scotland
Note how the Gogar Burn was significantly re-routed at some stage, presumably during the construction of RAF Turnhouse.