Australia Region | OPERATIONS | Gold Fields

 
Mineral processing and TSFs
 

  • St Ives operates a 4.7Mtpa processing plant that consists of primary crushing, SAG/ball milling, gravity and
    leach/CIP circuits.
  • TSF 1 has a Low ANCOLD consequence rating, was decommissioned and is being used for tailings
    reclamation for underground paste backfill material, using excavators, loaders and trucks.
  • TSF 2 has a Low ANCOLD consequence rating, was filled to the final design height and decommissioned.
  • TSF 3 has a Low ANCOLD consequence rating and was decommissioned in 2016.
  • TSF 4 is a paddock-type facility with a current maximum embankment height of ~14.5m. The facility is
    inactive and has a High C ANCOLD consequence rating.
  • The North Orchin in-pit TSF has a Low ANCOLD consequence rating, reached its storage capacity and was
    decommissioned in 2015.
  • The current active Leviathan in-pit TSF (with a Low ANCOLD consequence rating) has enough capacity to
    store the remaining LoM volumes.

 
The Agnew processing plant consists of a tertiary crushing circuit, followed by a two-stage ball milling
circuit with gravity and a conventional leach/CIP gold recovery circuit (1.3Mtpa capacity). The plant
capacity will be increased to 1.35Mtpa by the end of 2022.

Agnew’s TSFs 1 and 2, and an adjoined above-ground paddock storage facility, are decommissioned.
TSF 3 is an in-pit facility at the Redeemer pit, operational since it was commissioned in 2004. TSF 3 has
been irregularly topped up since commissioning TSF 4. TSF 4 is an in-pit facility located at the
Songvang pit and has a remaining LoM storage capacity of ~6.5Mt. All the Lawlers TSFs are closed and
rehabilitated.

 

Ore is processed at the milling/leach/CIP processing plant under campaign milling conditions located
15km north-east of the Wallaby underground mine. Granny Smith operates a single TSF complex that
comprises three compartments, known as cells 1, 2 and 3. A fourth cell (cell 4) will be constructed in
early 2022 next to cell 3 to provide additional tailings capacity for the rest of the LoM.

Cell 1 has a High B ANCOLD consequence rating and was raised to its final permitted crest elevation of
448m relative level (mRL) in late 2016. It has a remaining LoM storage capacity of ~0.80Mt and is
currently active.

Cell 2 was raised to its final permitted crest elevation of 448.5mRL in 2012. This cell has a High B
ANCOLD consequence rating, is filled to capacity and is harvested for paste fill.

Cell 3 has a High B ANCOLD consequence rating and is currently being raised to an elevation of
434mRL (final permitted elevation of 437mRL). The cell 3F lift will be completed by March 2022 and will
provide 1.97Mt capacity.

 

All ore mined is processed in the Gruyere plant, which consists of primary crushing, SAG/ball milling,
gravity and carbon in leach (CIL) circuits. The processing plant was designed to 7.5Mtpa but subsequent
work shows this can be increased to 9.262Mtpa for 2022 and then increased to 10Mtpa by 2024.

The TSF perimeter embankment is constructed in a downstream manner (in stages) to enclose a surface
area of ~203ha at Stage 1 (starter) and 231ha at Stage 6 (final). The TSF has a High B ANCOLD
consequence rating and a remaining LoM storage capacity of ~78Mt. Studies are in progress to extend
the existing TSF to increase capacity by 29Mt – 34Mt