Grzegorz Waluszkowski, 40, was helping to lay the pipe at the park on Lady’s Mile Farm, Exeter Road, Dawlish on July 23 2010, when the wall of the two metre deep trench caved in.

He was dug out by others at the scene before the emergency services arrived but had suffered multiple fractures to his skull, jaw and cheekbones.

The Health and Safety Executive prosecuted the park operators Main Gate Leisure after an investigation into the incident found the company had failed to adequately plan the work or put the necessary safety measures in place.

Torquay Magistrates’ Court heard Waluszkowski, who lived on the site, was working on the trench with two directors of Main Gate Leisure Limited.

The trench walls were propped-up with plywood and metal plate with a piece of softwood between the two sides holding them up. This gave way, and Waluszkowski was trapped when one side of the trench collapsed.

Frantic efforts were made by staff at the site to release Waluszkowski, who was unconscious, using shovels and eventually one of the directors used an excavator to help to dig him out from  the rubble.

HSE Inspector, Jonathan Harris, said: “The trench was clearly inadequately supported and the plywood and metal plate were no more than a rudimentary attempt to support the trench walls.

“Normally trench boxes would be used as shields whenever workers need to briefly enter a trench. These boxes can be rented from hire-companies.

“This incident could easily have led to a fatality and shows the vital importance of proper planning and adequate safety measures when carrying out this sort of work.”

Main Gate Leisure Limited, of Lady’s Mile Farm, Exeter Road, Dawlish, were fined £5,000 and ordered to pay £2,198 in costs.