Whilst completing other spider works on this site using the Menzi A91, we were requested to resolve a working access issue regarding removal and excavation on the lower section of the reservoir slip way in preparation for the planned replacement works.

The slip way was at an angle of approximately 38 degrees and we needed to remove 25m² of concrete and the sub-base to be excavated.

Main issues:

• Safe waste removal.
• Ensuring the spider excavator was in a safe position and unable to slide on the concrete slope.
• Ensuring the swapping from breaker to bucket could be safely and efficiently completed.
• Having a rescue plan in case of injury or illness.

We made use of the crawler crane on site to lift the 2-ton spider into position; it was also utilized for the removal of the excavated material. To ensure spider excavator and operator safety, the spider was secured using a winch line fitted to the small spider and a safety line was added using a suitably rated Tirfor winch.

We utilised a team of IRATA Rope technicians, allowing safe buckets changes. Using rope access recovery techniques, we established a safe rescue plan.

We completed this project ahead of schedule and on budget.