Bois des Rentes chamotte clay quarry – long-range planning & life-of-mine sequencing

Client & context

If you are responsible for a quarry like Bois des Rentes, your situation may look similar:

• You supply a central processing plant that relies on steady feed from several open pit clay quarries.
• You work with long-term contracts and specialised refractory products where quality and continuity matter.
• You operate in a mature mining district where land use, rehabilitation and local expectations are always in view.

In France, the main kaolin clay producer is Imerys Refractories (IRM, formerly AGS Minéraux), operating more than twenty quarries with around 1.5 million tonnes of annual production. The Clérac production centre alone processes roughly 400–495 thousand tonnes per year, fed by multiple active quarries. Bois des Rentes is the largest of these pits and plays a central role in the system.

At this stage, you want a life-of-mine plan and sequence that tell you how extraction and backfilling will unfold, how slopes and dumps will behave and how you will meet plant requirements year after year.

Challenge

On a quarry like Bois des Rentes, typical questions include:

• How do you sequence extraction so the plant gets the right tonnage and quality while you maintain safe slopes and haulage?
• Where and when do you backfill, so that you keep haul distances reasonable and support long-term land rehabilitation?
• How do you integrate geotechnical and soil mechanics information into everyday planning decisions?
• What does the full life of mine actually look like on a map, in sections and in a schedule?

In practice, you need long-range planning that connects geology, mine design, geotechnics, backfilling and production into one coherent picture.

Approach

The Bois des Rentes work was set up to give you the kind of long-range view that is hard to build from day-to-day planning alone.

Life-of-mine open pit quarry sequencing

You receive a life-of-mine plan that shows how the open pit will evolve over time:

• Definition of extraction phases that respect the geometry of the clay deposits and overburden.
• Sequencing of benches and panels to maintain an efficient mining front and manageable haul distances.
• Coordination of extraction with the expected needs of the Clérac processing plant.

This long-range sequence helps you see where you may face bottlenecks, higher stripping ratios or access constraints well before they become urgent.

Extraction and backfilling strategy

You also get a structured strategy for backfilling:

• Identification of zones suitable for progressive backfilling as extraction moves through the pit.
• High-level planning of volumes and timing so that worked-out areas can be filled in without disrupting active production.
• Support for rehabilitation and future land use, built into the mine plan rather than treated as a separate issue.

The aim is to keep the quarry compact and efficient while setting up a clear path for closure and long-term stability.

Geotechnical and soil mechanics input

Geotechnical investigation and soil mechanics information are used to:

• Check that slopes, benches and backfilled areas respect stability criteria.
• Guide design decisions for waste dumps and backfill placement.
• Reduce the risk of unexpected failures or ground problems later in the mine life.

The result is a life-of-mine design that does not just look good on paper, but also reflects the behaviour of the materials you work with every day.

Results & value

From this type of work at Bois des Rentes, you gain:

• A long-range open pit quarry sequence that links extraction and backfilling over the full life of mine.
• A clearer understanding of how the quarry will support the Clérac processing plant over time.
• Designs and sequences that are consistent with geotechnical and soil mechanics constraints.
• Study work delivered within the agreed deadline and to the client’s satisfaction, making it easier to move ahead with internal planning and external discussions.

For you, this kind of long-range mine planning provides a stronger technical basis for investment, production planning, rehabilitation and communication with authorities and local communities.