I was lucky? It was through a cable that hadn't been properly insulated before it was pulled out under the running and juice lines.
This was when I worked in the New Works Signalling Division at Southampton when they were single-lining the main line to re-line the tunnel. They found a stream under the tunnel no-one knew about! No hi-vis jackets or hard hats. Happy days!
We also worked near Brock (Brockenhurst) travelling down from Eastleigh every day with 2 cans of McEwans and a few games of crib to lighten the journey. Dinner was in the Brockenhurst Hotel.