The Farim phosphate deposit is a flat-lying sedimentary phosphatic bed, which underlies an area greater than 60 km2. The geological sequence at Farim displays the following lithological units from top to bottom:
• sandy-argillaceous overburden with soft, alternating sandy, clayey and sandy-clayey layers
• phosphatic interval (FPO)
• upper dolomitic limestone
• decarbonized phosphate unit (FPA) corresponding to the Saliquinhé phosphate deposit
• calcareous phosphate member (FPB)
• limestone at the footwall of the phosphate sequence, white, soft and porous.

Two main types of phosphate, differentiated by their petrography and chemical composition, have been identified on the Farim property:
• FPA layer – A de-carbonated phosphate matrix with very high P2O5 content of about 30% P2O5, formed exclusively in the shallow water of the Saliquinhé basin
• Lower grade FPB layer – Highly carbonated phosphate, generally containing 5 to 15% P2O5 (mean 13% P2O5) with some values up to 20%.

Deposit Geology and Mineralization
The three phosphate-bearing horizons referred to as FPO, FPB and FPA are located below a variable thickness of overburden.

Overburden
The overburden waste at Farim typically consists of a layer of reddish-brown laterite gravel, followed by cream-colored clay with occasional cobbles and boulders of cemented orange sand and brown clay. This is followed by a layer of stiff brown to ora ........

The FPA matrix is mined by a free-dig, multiple-bench, open-pit, haul-back mine using excavators and trucks.

For the 1.75 million tonnes per annum (Mt/a) (dry basis) open pit, it is planned that overburden will be stripped and removed with 12 cubic meter (m3 ) front-end loaders (FEL) matched with 97-tonne (t) capacity haul trucks. The matrix will be mined with 5 m3 bucket class backhoes matched with 36 t capacity trucks to minimize mining dilution and maximize matrix recovery. The matrix will be hauled to a 175,000 t (dry basis) ROM stockpile adjacent to the plant and segregated by quality. The matrix will be reclaimed and blended into a ROM bin by front-end loaders with 12 m3 buckets to achieve the desired plant feed P2O5 grade. The plant feed hopper will be installed so that haul trucks can directly feed matrix to the plant.

Overburden excavation will advance ahead of the matrix extraction in maximum 10 m height production benches. The overburden thickness ranges from 26 to 68m within the 25-year pit, multiple overburden stripping benches will be developed and maintained in advance of the matrix extraction. The matrix thickness ranges between 1.5 m and 6.25 m within the 25- year pit.

The most critical design element of the proposed mining plan is water management. All mining areas must be dewatered in advance of mining activities to allow sufficient depressurization and dissipation of pore water pressure and to accommodate dry mining of the ........

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