We did some work down in the tubes for tech many years ago. From a tech point of view everything that goes down there is considered to be limited life and possibly 1-2 years. It comes out black and coated even when it is put in racks with filters and seals. We won't talk about the rats in the tunnels, just do not ever get caught without a stick to make noise and a good lamp.
The temperature is also a know problem. Do a quick search on the interweb and you will see loads of what counts as modern investigative journalism! You might want to watch this with the sound turned off to just see the numbers for each line.
I have avoided the tube for years but it is just so practical as the car is now so hated in/by town.
Everyone loves a Morgan. Even me, unless it's broken again.