Prosecution Details

Being an employer failed, so far as was practicable, to provide and maintain a working environment in which its employees were not exposed to hazards; contrary to Sections 19(1) and 19(6) of the Occupational Safety and Health Act 1984.

The Defendant carries on a plumbing and drainage business that operates out of premises in Bunbury. In September 2003 the Defendant had a contract to perform in-fill sewerage work in part of Eaton, a suburb of Bunbury.

This work involved excavation of soil to create trenches of various depths, the laying of pipes in the trench and then backfill of the trench and rehabilitation of the area.

On 15 September 2003 employees of the Defendant were working in and around a trench located adjacent to the Eastern end of Pratt Road in Eaton. Another employee, was supervising the work. The trench was approximately 6 to 6 ½ metres deep and was dug in soil that was sand near the top surface and then at about 3 metres depth became sandy clay of varying consistency.

At the commencement of work on 15 September 2003 the part of the trench that had already been dug had a considerable quantity of water in it that had to be removed. As the trench was located close to the Collie River it was necessary to maintain de-watering equipment in the area in order to prevent water seeping into the trench.

Following the removal of built up water an employee operated an excavator to dig out the trench further along in an westerly direction adjacent to Pratt Road. As the soil was removed to sufficient depth the excavator, operated from within the batter, a short distance below the ground surface, was used to place a shoring box into the trench to prevent the sides of the trench from collapsing. The excavator then dug through the trench box to increase the depth of the trench to the depth where the pipe was required to be laid. When the trench was the correct depth, two employees entered the trench in order to lay the pipe.

The shoring boxes in the part of the trench where the two employees were working on 15 September 2003 extended from approximately 2 metres below the soil surface to approximately 2 metres above the floor of the trench. The top 2 metres of the trench closest to the surface had been excavated to a greater width (approximately 1 metre wider) than the remaining 4 to 4 ½ metres of trench. There was no shoring method used to support the soil from the base of the trench to approximately 2 metres high.

An attempt was made to push the shoring boxes down further by applying force to them with the excavator but this was unsuccessful partly because the excavator operator was limited in his ability to manipulate the shoring boxes given the excavator's position.

On 15 September 2003 at least one employee expressed concerns that the shoring boxes were too high above the floor of the trench and the trench was too vertical giving rise to a danger that the unsupported lower walls of the trench could collapse onto persons working in the trench.

At approximately 2:45pm on 15 September 2003, while the two employees were working in the trench part of the wall of the trench collapsed into the trench. One of the employees was hit by a quantity of soil and suffered fractured ribs, right clavicle and shoulder. He is still undergoing rehabilitation and has been advised by his surgeon that he cannot return to his pre-injury job.

It would have been practicable for the Defendant to take one or more of the measures outlined in the particulars of the complaint.

The Defendant pleaded guilty.