These wells are well-suited to alluvial formations that include bank gravel or pebbles in a low depth – high flow setting (Rhône valley type, Durance).

They are made of a concrete watertight lining, 3 to 4 meters in diameter, equiped with weep holes (PVC openings) across the water table.

The watertight lining’s construction is made on-site with 2 meters tall blocks, cut with a grapple.

This kind of well allows for high flow rates by realizing tens of meters drains ending up in the collecting well.

Its creation first of all requires the construction of a concrete watertight lining, poured on-site by our staff and cut all the way up to the substratum (up to 30m deep).

After the bottom concrete apron instalaltion, the well is drilled across the drains to be. The later are then drilled from the inside by a specfic workshop requiring a high technical level.

The well is then equipped with control valaves (one per drain) and a safety flooring with an access ladder. Every item are up to the sanitary norms.

The Grand Chalon well

Realization of wells using Benoto excavation technique

We produce 600 to 1500 mm wide structures up to 50m deep in alluvium.

We do not use any fluids (water, mud, or compressed air) : this neutral drilling technique doesn’t disrupt hydraulic flows. Overdrilling is avoided and cuttings recovering is made easier: we use overburden drilling techniques. Result : the equipment is adapted to the local geology.

In order to do so we have the following machines at your disposal ,

• 1 LIEBHERR 8030 crane
• 2 CASAGRANDE C200 cranes
• 5 CASAGRANDE GC1500 casing oscillators
• Retaining pipes ø680 to 1540 mm wide

The Satigny drilling

The Satigny drilling is the first medium depth exploration drilling for the 2020 Géothermie program. This pilot project will allow to outline the sector’s geothermal potential and to assess field work reality. Other similar drillings will be under way in the Canton until 2020. The new knowledge that will be acquired along the way will allow us to drill deeper than 1500m.

The Satigny drilling’s goal is the exploration of Cretaceous limestones up to a depth of 650m. As it goes on, it allows us to identify the underground’s geological and hydrogeological conditions. We expect, from 400m deep onward, areas with faults allowing the circulation of hot water, offering a potential geothermic resource.

From a technical point of view, it is one of the few water structure made with techniques coming from the oil industry, under permanent quality control.

For more informations : Site Géothermie 2020