Cumbrian coal mine

[AE-NMidlands]

the coal will be heated in an anaerobic atmosphere to drive off the gases, leaving behind fairly pure carbon as coke. This used to be how all our town gas was made,

This is the three legs of the economy that grew the railways, raw coal to town gas plants, coke to steelworks and then steel to towns.

I'm not so sure about that, (may be splitting hairs here, but) coke is very light, so it's wasteful to move it by rail: some was and the wagons were as wide and as high as possible - and were still only 20 tons gross. (Hence not a very attractive traffic.)
However a) there was a high demand for heat at steelworks (pre-heating blast furnace air and driving the coke ovens too) so on-site coking ovens were common,
b) coke was sold as a by-product from town gas works for domestic fuel, and
c) I suspect more brick and slate were used in building housing than steel...

Our house is late Victorian and I'm sure the bricks were fired very locally (like using clay dug from a pit in the field behind) but the freight moved would have been coal, timber from ports to local merchant - and lead pipe and other castings like the bath, taps and door furniture which again would have moved by rail to local merchants and builders yards.
I'm pretty sure that the lions share of freight traffic was just coal. Some other specialist things like a few fish trains each night, but there was apparently a continuous procession of coal trains towards London from all the coalfields within reach. Cast (pig) iron and steel sections would have gone as wagonload traffic to the station or private siding nearest where it was wanted.

[openspaceman]

This is the three legs of the economy that grew the railways, raw coal to town gas plants, coke to steelworks and then steel to towns.

I'm not so sure about that, (may be splitting hairs here, but) coke is very light, so it's wasteful to move it by rail: some was and the wagons were as wide and as high as possible - and were still only 20 tons gross.

Well it's an old memory from geography lessons long ago so no cites.

Of course as steel making became more integrated it would make sense to use all the energy from the coal just as later on all the coal was used at major gasworks with a two stage swing process that resulted in our town gas having 10% nitrogen.

[Djs63]

Perhaps the government plan to bury radioactive waste in the mine