I was on a small building site with about 10+ workers, 2 weeks ago in Cheltenham and watched a worker on the 'scree pump' make scree.  20 Shovels of sand, one and a half bags of cement and a large bucket of water.  This was then mixed in a rotating drum and then pumped to where it was needed.  Cement dust was blowing in the wind and the worker was both covered in it and breathing in some of it - it can't be stopped at the moment with that method in use. Added to this was the constant very loud drum of the engine and the diesel fumes wafting about.  It was back breaking work just looking at it.  So is there a better way?