Can't find any aerial pics (yet) of the West Sleekburn Colliery. The old maps show a few buildings but they aren't always reliable.
The Durham Mining Museum (DMM) site records the first output of coal as 1882 and the first map I can find with the colliery on is 1898 and it shows an air shaft in the area of the building you are looking at @Gary Park. If I find any aerial photos, and I remember why I'm after them, I will post them