Roofbolters

At the Rhododendron Festival.
This is the national roofbolting championship, so it's quite a big deal, with respectable amounts of prize money involved.
There was a night session last night and the finals this afternoon. The night session has quite a different atmosphere - trisharooni took a fabulous night shot back in 2006 (I think), in the mist. It gives a bit more idea of how the thing works as well as being a great photo.
(This is another of my all-time favourites of hers, by the way, from the same year.)
Roofbolting is a thing they do down in the mines - they use these machines to drill up into the roof of the tunnel and put in long bolts. This helps to hold the roof together so cracks don't cause sections to fall in.
Mines from all over the country field two man teams in the competition. Two teams at a time race each other to carry the machine, drill bits and bolts to the "roof" (a hefty block of concrete atop a permanent steel structure in the pub carpark), drill up into it and insert the bolt. Whichever team is fastest gets the points. The bolts are a metre or so long. In this shot, a team is checking over their equipment ready for the next round - and discussing their strategy, by the look of it.
There's water and concrete mud and clanging of steel and hydraulics hissing - it's all very blokey and exciting and the pub does a roaring trade in beer at the outdoor bar. It's a very popular event. There seem to be quite a lot of roofbolting 'groupies' too. Not sure I'm not one myself really.