Making a wild assumption that you use ropes to descend and ascend wells...
In the commercial sector rope access is generally governed (and training defined) by the "Industrial Rope Access Trade Association"
www.irata.org
I would imagine your insurance (?) would stipulate IRATA training?
We're a non-commercial club so we're outside that remit.
Rope access equipment is of course widely available and in many instances commercial and non-commercial equipment is the same.
Perhaps you can give a bit more information about how you go about your work at present - i.e. do you work off ropes at all?
General Health and Safety issues are standard and apply across the board, just Risk Assess and go from there.
www.hse.gov.uk/ would be the place to go for information / advice.
If its hands on help/technical advice you want, regarding 'going underground' feel free to ask any specific questions and i'm sure we'll all waffle on with loads of practical 'amateur' 'advice'.