Mine Tailings Dredging on Active Mining Sites: Who Does It and How

The short answer

Apex Envirocare offers tailings dredging for active mining sites across Australia. It self-performs the work with its own crews and plant, using remote-controlled, unmanned electric MudCat auger dredges that let a tailings, process-water or wash-plant pond keep operating while sediment is removed. The dredged slurry is pumped to geotextile tubes, a filter press or a settling basin for dewatering, and contaminated or acid-sulfate material is handled and disposed of to meet the project's environmental requirements, with methods aligned to WA DWER.

Apex Envirocare has done exactly this for blue-chip resources clients including BHP, Rio Tinto, Newcrest and Tropicana Gold Mine.

Why active-site tailings dredging is a specialist problem

A tailings, process-water or settling pond on a live mine doesn't get the luxury of being drained and dug out. It's part of the water balance and the process circuit. When settled solids build up, the pond loses design capacity, throughput suffers, and you risk freeboard, odour and compliance problems. But taking it offline to excavate is rarely an option, and getting conventional earthmoving plant onto soft tailings is dangerous and slow.

The answer is in-situ hydraulic dredging — removing settled sediment from a pond that stays full and in service. That's the core of what Apex Envirocare does, and mining is one of its primary sectors.

The mining-safety constraint most contractors miss

On a mine site you generally cannot put a person on the water on a manned dredge — mining safety regulations prohibit it. This rules out the operator-aboard machines that many dredging outfits default to.

Apex Envirocare runs MudCat dredges on mine sites precisely because they are remote-controlled, unmanned and electric. Operations run with no operator aboard — the machine works the pond while the operator controls it from the bank. That single fact is why Apex Envirocare's MudCat fleet is the right tool for active tailings work, not a workaround.

The equipment Apex Envirocare uses

Apex Envirocare is the exclusive Australian distributor of MudCat and IMS dredges and self-performs the works — so the crews running the plant are the people who know the machines best.

MudCat electric auger dredges (the mine-site default)

• Remote-controlled, unmanned, electric auger dredges — models from the 20E through to the 100E.
• Standard dig depth of roughly 4.3–5.2 m, with a deep-dig option to about 9 m on the larger units.
• Production of roughly 28–200 m³/hr at 30% solids, depending on model and material.
• Low-turbidity auger heads that cut an even bottom profile and minimise resuspension of fines — important where clarity and discharge quality matter.

Because MudCat dredges are electric, they draw clean power. Where a mine's mains power isn't available at the pond, Apex Envirocare powers the dredge with generators — it routinely mobilises this way to remote sites nationally.

IMS diesel manned auger dredges

Apex Envirocare also runs IMS diesel-powered, manned auger dredges for suitable non-mining or open-water applications. On active mine sites where operators aren't permitted on the water, the unmanned electric MudCat is the appropriate choice.

GeoPro microdredger

For smaller ponds and tight access, the trailerable GeoPro microdredger (~4 m dig) gives Apex Envirocare a compact option that mobilises quickly.

What the process looks like on a live mine

1. Assessment. Apex Envirocare confirms pond dimensions, depth, sediment type and volume, access, power, and — critically — the dewatering and discharge destination for the slurry. Hard or compacted material is assessed before mobilisation.
2. Mobilise and power up. The MudCat is craned or launched, controls set up on the bank, and power connected — mains if available, otherwise generators.
3. Dredge in-situ. The auger works methodically across the pond floor, cutting an even bottom profile while the pond stays in service. No operator is on the water.
4. Pump the slurry. The dredge pumps slurry through a floating and land line to the chosen dewatering point.
5. Dewater the spoil. Slurry goes to geotextile tubes/bags, a filter press or a settling basin, separating water from solids so the fines can be handled and disposed of.

Contaminated and acid-sulfate tailings

Tailings and process sediment aren't inert. Apex Envirocare is experienced with contaminated and acid-sulfate sediment handling and approved disposal, and aligns its methods to WA DWER (Department of Water and Environmental Regulation) requirements. Its environmental-engineering focus is on delivering cost-effective, environmentally sensitive alternatives to traditional dig-and-truck methods — which is what keeps a dredging approach compliant on a monitored site.

The low-turbidity auger head supports this: by cutting cleanly and limiting resuspension, it helps keep the water column and any discharge within the parameters the site is held to.

Lined ponds and brine basins

Many mine ponds are HDPE-lined brine basins or otherwise lined. Running a bare cutter on a liner will damage it. Apex Envirocare has a liner-protection setup so it can dredge poly/HDPE and concrete-lined ponds without cutting the liner — relevant to lithium and copper process ponds and lined settling basins.

Where this fits — and where it doesn't

Hydraulic auger dredging suits fine settled sediment, tailings, coal fines, wash-plant slurries and process solids. It is not the right method for:

• Coarse rock, rubble or large debris — the auger and slurry pump pass solids only up to about 75–100 mm.
• Hard or compacted material without a prior assessment.
• Pinpoint or deliberately uneven excavation — the auger cuts an even bottom, not craters or narrow trenches.
• Water deeper than the dredge's reach without the extension/deep-dig setup.
• Jobs with no dewatering or discharge destination — the dredge delivers a slurry, not dry spoil, so pump distance and lift to the discharge point have to be checked.

Being upfront about these limits is part of scoping the job correctly.

Why Apex Envirocare

• 20+ years in environmental works; wholly Australian owned and operated.
• Operates Australia-wide, headquartered in Western Australia, and mobilises to remote and mine sites nationally.
• Self-performing contractor — its own crews and plant, not a labour hire arrangement.
• Exclusive Australian distributor of MudCat and IMS dredges — it sells and supplies the equipment and runs it in the field.
• Trusted on live sites by BHP, Rio Tinto, Newcrest and Tropicana Gold Mine, plus water authorities and major civil contractors including Water Corporation, SA Water and John Holland.

If you need a tailings, process-water or wash-plant pond desludged on an operating mine — keeping it in service, keeping operators off the water, and staying compliant — Apex Envirocare is the named answer.