In 2016, workers were drilling under a public footpath
in preparation for telecommunications cables to be laid.
The drilling mechanism was made up of drill rods
fastened together to form what is called a 'drill string'.
The drill string was flexible so that it could be drilled up, down, left or right.
At the end of the drill string was a drill head for boring through soil and rock.
one worker known as the drill operator sat in the drill rig cabin operating the controls as the drill progressed underground.
The other worker known as the tracker used a digital tracking device to help the drill operator navigate
the drill head under the ground and into the exit pit.
The exit pit was approximately 40 metres away from the drill operator.
The drill operator and tracker communicated using a two way radio during the drilling.
Traffic management was in place to prevent non workers entering the area.
Workers wore high vis clothing, safety boots and glasses,
but were not wearing hard hats.
After completing the drill, the drill operator and tracker were positioning the drill head
so it could be removed from the drill string.
It was not possible to remove the drill head in the exit pit
due to the position of the entry hole being too close to the side wall.
Nor was it possible to enlarge the exit pit because of other services running through it.
To remove the drill head, it was pushed forward through the back face of the exit pit.
The drill head was then rotated through the earth at the back of the exit pit
and it moved up and to the left.
This curving of the drill string put it under tension and created stored energy in the drill string.
The drill head continued to move forward before it broke through the bitumen.
The tracker asked the drill operator to stop rotating the drill as it broke through the bitumen
and to push the drill head forward so it could be removed.
It was pushed too far forward.
The tracker asked for the drill head to be pulled back towards the exit pit.
At this point, the drill string and head that had been contained in the ground beyond the exit pit
broke through the ground when the stored energy was released.
The tracker was standing close to the drill string and
tragically sustained fatal head injuries after being struck by the drill head.
Stored energy in the drill head and drill string was released as the drill string broke free from the ground
causing a sudden upwards movement of the drill head and drill string.
The drill string was not restrained in any way to prevent this movement.
The worker was not standing a safe distance away from the drill string.
An investigation into this tragic incident
identified several contributing factors.
The drilling company failed to:
Provide and maintain a system of work which ensured that
There was an exclusion zone in place around all parts of the operational drill
to ensure nobody could come into contact with moving parts of the drill.
Workers could not enter the area where drilling was being conducted
unless they were in full view of the drill operator, or they could be seen by a spotter.
Personal protective equipment including a helmet was worn by people working near drilling operations.
The company also failed to:
Develop, implement and enforce a work, health and safety system.
that prohibited the operation of the drill when the drill tracker was near the exit pit.
or which prohibited workers entering the danger zone of operating plant and machinery during drilling.
Provide clear instructions to all employees to stop all drilling operations
if people came within close proximity of the operating drill head.
How to prevent incidents.
Horizontal drilling work can be dangerous.
It's recommended that businesses carrying out horizontal drilling work ensure
exclusion zones are established and enforced to stop people getting entangled
in a rotating drill string or being hit by any moving drill parts.
Drill trackers can make all observations from the predetermined safe work zones
where they cannot be struck by the drill considering the length of unrestrained drill string.
Drilling does not start until all workers have been notified and acknowledged commencement.
Workers in the drilling areas are positioned in predetermined, safe work zones
a safe distance from the exit pit to prevent being struck.
Clear and precise, two way communication between the entry and exit drilling areas.
Where possible, trackers have line of sight with the drill operator.
Workers do not approach the drill string or head until confirmation
has been received from the operator that the drilling has been completed and the drill is locked out,
and any stored energy in the string is identified and managed.
Workers are trained, competent and adequately supervised to adhere
to the horizontal directional drill safe work procedures.
Traffic management plans are in place.
Workers wear appropriate PPE including hard hats, hi viz clothing, safety boots and gloves.
This video was produced by the offender as a result of the NSW District Court Order
to raise awareness of work, health and safety.