Sainte Foy Tarentaise : 28 July 2020
Luckily for me, I was running a little late with my early morning run today. I didn’t get to Plan Bois until 07h00, just as the workmen were arriving, and there was already a lot of activity.
As is my want, I had a quick chat with them and asked my usual question about when the next helicopter day was due. “Normalement c’est aujhourd’hui”, came back the reply, ‘it should be today’.
I’ve been waiting to see some helicopter action, so I was more than happy to run back home, grab my phone, and race back up to the top of Aprpettaz to take some photos. It was a little more exercise than I’d pencilled in for today’s training session though!
Italian owned French company, Poma, (also known as Pomagalski), is the lift manufacturer on this project. You may recognise their name as that used for the eponymously named button lift, ‘a Poma lift’.
COMAG, also based in the French Alps, specialise in the installation of cable transport systems, and has been chosen for their expertise in operating in difficult terrain.
Today’s job was to lay the concrete foundations for the ten pylons on what will be the new Arpettaz chairlift.
Each pylon has had its spot marked out, a hole dug, and the highlighter spray used to mark the exact dimensions of where the concrete base will be placed.
The bottom part of the base is 2.5 m², and fixed on top of that is a 2 m high block of concrete containing metal reinforcements and a metal cage to which the pylon will be attached. Anthony Deparis and Camille Jordan are stood on top of the casing into which the concrete will be poured.
The photo below shows the metal cage in the foreground, and a preformed concrete base pad with concrete uprights, all of which contains metal reinforcement.
Including the base station and the landing area, a total of 350 m³ of concrete will be used. That’s a lot of concrete, and there was a constant flow of concrete lorries driving up the mountain.
It works best, and is more economical, for the lorries to bring the concrete up to the top of the Arpettaz lift, and for the helicopter to then take it down to each pylon base. This saves helicopter fuel costs, and saves time against what is a very expensive hourly rate.
The whole operation is very carefully choreographed, and designed to maximise the usefulness of the helicopter.
Here is a video of the helicopter delivering concrete to the ninth pylon. The helicopter will deliver twenty loads of concrete in metal hoppers, and each time it arrives, the two workmen pull a handle to release the concrete when it is correctly lined up. The pilot’s precision is breathtakingly accurate.
Whilst the delivery takes place, other men are reloading the spare hopper with more concrete. This next video shows the helicopter dropping off the empty hopper and picking up the reloaded one. Again, the flying skills and precision of the pilot are remarkable indeed.
All this will eventually be buried underground, but we now know that each pylon has a reassuringly heavy, nine tons of concrete pinning it to the mountain. Even the most vicious of winter storms won’t be able to budge them!
As you can see from the photos, the weather was all sunny first thing morning, providing perfect conditions for the concreting. But as we all know, it can change very quickly in the mountains, and as I sit in front of my laptop writing this, there are cloudbursts of rain accompanied by thunder and lightning outside.
This is one of the ways the planning can very quickly be thrown off course for this sort of high mountain building project. There aren’t many helicopter pilots who would volunteer to dodge bolts of lightning in a thunderstorm!
Read other articles about Sainte Foy on the Time to Ski blog page
