Drill Site With a View - Hout Bay

It is always exciting to take on a new challenge, but it’s not often that challenges come with such a spectacular but distracting view as in the case of this geotechnical contract in Hout Bay that we conducted.

Military Road in Hout Bay is a tiny narrow tree-lined street, situated high up on the hillside only accessible from Chapmans Peak Drive. The site which is situated on an incredibly steep 40-degree slope with panoramic views of Chapmans Peak pass, the picturesque beach, the colourful harbour, and Sentinel Hill in the background. While being surrounded by so much beauty and spectacular views, we knew there were difficult challenges that lay ahead. 

The request was to drill a borehole located at the crest of the slope but without impacting on the single-lane road that serviced the residents & guest house. The only option we had was to position our drill rig & equipment two meters off the edge of the steep slope allowing for sufficient space to accommodate the traffic and to allow us to drill safely. 

The challenge was that we had a 40-degree slope which descended from the slope side of the curb stone which lined the single narrow road. Our only solution was to erect some form of an elevated platform that could safely support a 2Ton drill rig, four crew members and approximately 300kg’s of drilling equipment & consumables with enough safe working space. Faced with these sorts of challenges it is always best to call on the experts hence the introduction of Peter Harper from Alpine Scaffold. 

After a lengthy site visit and numerous hours at the drawing board, Peter formulated a design for an elevated platform that would safely support our requirements. There were however other obstacles we had to overcome like anchoring the elevated platform without restricting any access to the narrow single road at the same time making sure it could accommodate the required weight of our drilling operation. 

A combination of lateral supports, ladder beams, scaffold jacks, spreader plates and a wooden deck made up a sturdy platform that was load tested to twice the required capacity with compelling results. With the elevated platform successfully in place, the last challenge was to reverse a MERC 4x4 crane truck down a narrow tree-lined single road with protruding obstacles to sling the drill rig onto position. 

With the drill rig securely in place and a 500cm x 500cm hole cut through the wooden deck, all that remained was to construct our circulation sumps approximately 1.5m below the working surface on the 40-degree slope, this was constructed by using sandbags, a plastic liner and pvc pipes. The sumps we completed and in perfect working order.

During the course of the next two days the team drilled and conducted in-situ SPT testing throughout the length of the borehole. Usually, we drillers find ourselves taking teatime or a lunch break under the shade of a tree or hiding from the heat in the back of a vehicle but not in this case. With legs slung over the edge of the raised platform, sitting securely behind the guard rail, enjoying the tranquillity and amazing views that so many people around the world would pay fortunes to experience.

After a successful drilling campaign, it was back to the challenge of undoing everything we had carefully assembled. There is just as much risk, possibly more after a vigorous drilling schedule, when removing a drill rig with a truck-mounted crane in limited space and dismantling an entire elevated platform on a 40-degree slope. The drilling crew set to work and safely demobilized the drill rig and all equipment from the elevated drilling platform. 
The circulation sumps and drill site were rehabilitated in preparation for the specialized crew from Alpine scaffolding to start the dismantling of the elevated platform.

A combination of communication, procedures and a safe professional approach to a difficult challenge made what seems uncertain and difficult surprisingly easy to accomplish.

With the right preparation and attitude, you can overcome any challenges you are faced with.