Employee Kevin Trump was working on backfilling a raised roadway in Swansea when the accident happened.
He was using an improvised earth ramp to access the area which was adjacent to an excavation
But the ramp gave way under the weight of the roller allowing the vehicle to slip into the hole.
Trump was able to release his seatbelt but fell head-first into the hole suffering severe flesh and muscle injuries.
Randalls Groundworks pleaded guilty to a failure to ensure the safety of employees contrary to Section 2(1) of the Health and Safety at Work Act 1974.ADVERTISEMENT
It was also ordered to pay costs of ВЈ8,244.47 at Swansea Crown Court.
Health and Safety Executive inspector Steve Richardson said: "Mr Trump suffered serious injuries but the outcome of this incident could have been considerably more serious as the roller came to a halt directly above him on the slope.
"There were no barriers in place to mark the edge of the excavation and Mr Trump had never received any training on the roller he was operating.
"This incident highlights a number of health and safety issues. It is imperative that training is given on specialist equipment."
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