"as always" is correct but it would be interesting to see your trans of the whole sentence.

I would propose "like in former times" - "as always" can mean that they work in the mines on let's say Christmas just like the rest of the year, which is probably not what is meant here, but rather that they work there nowadays just like all those years before.

(in this contexts the miners go into the pit day in, day out)

yes, ioreth, upon further consideration, you are right! Here are some more suggestions.