Volumetric Uav — Gladstone

TL;DR: A drone volumetric survey in Gladstone measures the coal, bauxite, alumina and aggregate stockpiles that pass through Port Curtis to 1-3% volume accuracy, flown in hours instead of days and with nobody climbing a loose pile. Industrial Spatial Solutions flies CASA-certified RTK UAVs across the RG Tanna coal terminal, the Yarwun and QAL bauxite-residue precincts and Central Queensland mine sites, then reports cubic metres and tonnes a registered mine surveyor can certify.

Key takeaways

• Gladstone moves more than 67 million tonnes of cargo a year — coal through RG Tanna, bauxite and alumina through Barney Point and the refinery precincts — and every tonne booked as inventory needs a defensible volume; a drone volumetric survey delivers 1-3% accuracy against the 3-5% of a GPS walkover.
• ISS flies RTK/PPK UAVs (DJI Matrice 350 RTK with the Zenmuse P1 for photogrammetry and the Zenmuse L2 for LiDAR) under a CASA Remote Operator's Certificate, with control and check points reduced to GDA2020/MGA2020 and AHD.
• A whole stockpile pad at a Gladstone terminal — a dozen or more piles — is captured in a single morning's flying and reported within 24-48 hours, without halting reclaimers or loaders.
• The base-surface decision (surveyed toe plane, prior survey or design pad level) moves the reported volume more than instrument accuracy does, and on a sealed terminal pad versus a loose mine ROM stockpile that decision is different — ISS states it in every report.
• Coal, bauxite and alumina each carry distinct bulk densities and moisture behaviour, so the volume-to-tonnes conversion is the largest error source and is documented with its source on every Gladstone job.

Drone volumetric surveying in the Gladstone region

Gladstone exists to move bulk material. Port Curtis is Queensland's largest multi-commodity port and the fifth-largest in Australia by tonnage, and the bulk of what crosses its wharves spends time as a stockpile first — coal banked at RG Tanna before a Capesize berths, bauxite staged ahead of digestion at Yarwun, alumina holding before it loads for Boyne Island or export. Each of those piles is a number on a balance sheet, and the accuracy of that number is exactly what a drone volumetric survey exists to protect.

The case for flying these stockpiles rather than walking them is sharpest in Gladstone precisely because the volumes — and the values — are so large. A 5% error on a 500,000 m³ ROM coal stockpile feeding the Goonyella or Blackwater rail systems is tens of thousands of tonnes, and at metallurgical coal prices that is a multi-million-dollar misstatement in a single inventory line. A GPS rover crew can only record points where a person can safely stand; the steep, segregated faces where the error concentrates are the parts you cannot walk. A UAV captures the whole surface uniformly in minutes, from a safe stand-off, with no plant interaction.

This page covers how ISS delivers a survey-grade drone volumetric survey across Gladstone and Central Queensland: where it is used, the method and kit, the accuracy and standards behind the number, and why a survey firm — not a general drone operator — is the right partner for a port stockpile that has to withstand audit.

Key point: On a Gladstone terminal, the volume is rarely the hard part — the toe is. A sealed, level RG Tanna pad gives a clean, surveyable base surface; a loose waste dump at a Bowen Basin feeder mine does not. The same UAV produces a defensible number in one case and a confident guess in the other unless the base surface is measured rather than assumed.

Local applications and sites

Gladstone's industrial concentration means a single mobilisation can cover several distinct volumetric jobs across very different material.

Coal at RG Tanna and the export chain

The RG Tanna Coal Terminal handles over 55 million tonnes of coal a year, fed by the Moura, Blackwater and Goonyella rail systems out of the Bowen Basin. Product and blend stockpiles on the terminal pad are reconciled against rail-in and ship-loaded tonnages; a repeatable monthly flight gives that reconciliation a stable baseline and exposes drift between weightometers, draught survey and booked inventory. ISS flies the pad between vessel cycles, captures every stacker-built cone and windrow, and reports per-pile volumes against the surveyed pad level.

Bauxite and alumina at Yarwun and QAL

Rio Tinto's Yarwun refinery and Queensland Alumina Limited (QAL) — one of the world's largest alumina refineries at over 4 million tonnes per year — stage bauxite ahead of digestion and hold alumina product before dispatch. Bauxite is dark, dusty and often low-contrast, which is where the LiDAR payload earns its premium: it measures range directly and returns bare-earth points where photogrammetry would smear the surface. Residue and bauxite-residue storage areas also lend themselves to UAV survey for capacity, freeboard and landform monitoring.

Aggregate, cement and laydown

Cement Australia's Fisherman's Landing operations, regional quarries supplying construction material, and the laydown yards that serve Gladstone's continuous capital works all hold aggregate, sand and clinker feed stockpiles. A fortnightly or monthly flight keeps booked inventory honest and supports per-cubic-metre progress claims on civil works.

Central Queensland mine feeders

Beyond the port, the Bowen Basin operations that feed Gladstone — BMA's Blackwater, Goonyella, Peak Downs and Saraji, and Anglo American's Callide and Kestrel — generate continuous volumetric demand: monthly ROM and product inventories, overburden and waste-dump movement for contractor payment, tailings storage facility freeboard, and short-interval pit progress between formal mine surveys. ISS mobilises to these sites as part of the same Central Queensland programme.

Method and equipment

ISS runs the same repeatable, survey-grade workflow on a Gladstone terminal that it runs on a remote mine pad. Every flight is conducted under our CASA Remote Operator's Certificate (ReOC) by a licensed remote pilot (RePL), with a Job Safety Analysis and site induction completed first — and at a port, with port security clearance and coordination with the terminal operator's traffic and vessel schedule.

Flight planning. We confirm the targets, the accuracy target, the base-surface methodology and the deliverable format, then design the flight in advance. Photogrammetry missions are planned at 70-80% overlap and a ground sample distance matched to the tolerance — typically 1.5-3 cm/pixel. Airspace is checked carefully in Gladstone: the LNG plants, the port and Gladstone Airport all impose constraints that are resolved before mobilisation.

Ground control. Control and check points are observed with a Leica GS18 GNSS receiver or total station and tied to site control or MGA2020. RTK/PPK on the airframe reduces the control needed, but independent check points are always retained — RTK can produce a precise model that is systematically shifted in the vertical, and only a withheld check point catches that before the volume is reported.

Capture. The DJI Matrice 350 RTK flies the grid autonomously — IP55 sealed, around 55 minutes endurance, which matters in Gladstone's heat and humidity. The Zenmuse P1 (45 MP full-frame) captures imagery for open, well-textured coal and aggregate piles; the Zenmuse L2 LiDAR payload is flown for dusty bauxite, vegetated residue areas and overcast conditions.

Toe and base surface. The boundary between pile and pad is where volume error lives. On a sealed terminal pad we survey or confirm the pad level as the base surface; on loose ground we observe the toe directly. For change-detection work the prior survey or design surface is registered as the base instead.

Processing and QA. Imagery is processed into a dense point cloud and digital surface model in Pix4Dmapper or Propeller Aero; LiDAR is classified to bare earth. Volumes are computed in Propeller, Trimble Business Center or the Australian-developed 12d Model, checked against independent check points, cross-sections and visual inspection before release.

Key point: RTK and PPK reduce ground control on a Gladstone job but never eliminate the check point. A coal stockpile reconciliation that feeds a quarterly inventory position has to be auditable, and the only thing that makes a UAV volume auditable is an independent point withheld from the solution.

Accuracy and standards

A well-controlled drone volumetric survey achieves 1-3% volume accuracy on typical stockpiles, with positional accuracy on the surface model in the 20-50 mm range depending on GSD, control and payload. The volume percentage is what the inventory team cares about; the positional accuracy and the documented method are what make the figure defensible.

ISS operations are governed by the Civil Aviation Safety Regulations (CASR) Part 101 and conducted under our CASA ReOC; all pilots hold a RePL. Deliverables are referenced to GDA2020/MGA2020 and AHD and reduced consistent with the ICSM Standards for the Australian Survey Control Network (SP1), so the output drops straight into your site datum. Where the work feeds statutory mine survey records for a Bowen Basin feeder operation, results are provided in a form a registered mine surveyor can certify, consistent with Queensland's Mining and Quarrying Safety and Health Act 1999 and the recognised-standard survey requirements that sit under it.

Accuracy is verified, not asserted. Independent check points withheld from the solution are used to report residuals in the deliverable, and bulk density — the single largest source of error when converting coal, bauxite or alumina volume to tonnes — is stated explicitly with its source.

Why ISS for Gladstone

A general drone operator can produce a point cloud; a survey firm produces a number you can take to an auditor. That distinction matters more in Gladstone than almost anywhere in Queensland, because the stockpiles here sit on the financial books of Rio Tinto, BMA, the LNG joint ventures and Gladstone Port Corporation, and the volumes are large enough that a careless 5% becomes a board-level conversation.

ISS brings licensed survey discipline to every flight: we observe and reduce our own ground control, retain independent check points, reference everything to MGA2020 and AHD, and report accuracy and bulk density transparently. We are independent and multi-platform — photogrammetry or LiDAR chosen on the merits of the material, processed in the package best suited to the job, handed back in your CAD, GIS or mine-planning format (12d, Trimble, AutoCAD, Surpac and similar).

We also understand the Gladstone operating environment: continuous operations that cannot stop, port security and traffic constraints, LNG and refinery airspace, cyclone-season weather windows, and shutdown schedules at the smelter and refineries. We mobilise directly to Gladstone from our Queensland operations and integrate the volumetric into a coordinated survey programme rather than treating it as a standalone visit. For operators running stockpiles across the port and feeder mines, that means one team, one datum and one reporting standard across the whole supply chain. The Gladstone industrial survey hub covers the full range of mechanical, engineering, UAV and laser-scanning services available across the region.

Frequently asked questions

How accurate is a drone volumetric survey on a Gladstone coal stockpile?

With surveyed ground control, independent check points and a clean pad toe, ISS achieves 1-3% volume accuracy on typical coal stockpiles — better than the 3-5% of a GPS walkover, because the UAV captures the whole surface uniformly instead of interpolating between walked points. On a sealed RG Tanna-style pad the base surface is well defined, which helps the toe; the accuracy is reported against withheld check points, not assumed.

Can you fly while the terminal or refinery is operating?

Yes. Flying is conducted at a safe stand-off under a site-specific JSA, CASA conditions and port security clearance, usually without halting reclaimers, loaders or plant. We coordinate exclusion zones, pad access and vessel timing with your operations team. We do not fly in rain or high wind — both degrade data and breach our safety conditions — which in Gladstone means planning around afternoon sea breezes and cyclone-season systems.

Coal, bauxite, alumina — does the material change the method?

It does. Open, well-textured coal and aggregate suit photogrammetry with the Zenmuse P1. Dark, dusty, low-contrast bauxite and vegetated residue areas favour the Zenmuse L2 LiDAR payload, which measures range directly and returns bare-earth points through dust and light cover. Bulk density and moisture also differ markedly between commodities, so we document the density and its source for every volume-to-tonnes conversion.

Can ISS cover both the port stockpiles and the feeder mines?

Yes. We mobilise across Central Queensland from our Queensland base and routinely combine port terminal work at Gladstone with Bowen Basin feeder operations — Blackwater, Goonyella, Callide and others — in a single programme. One team, one datum (MGA2020/AHD) and one reporting standard across the supply chain make reconciliation between mine, rail and ship far cleaner.

Request a quote

If you need coal, bauxite, alumina or aggregate stockpiles measured quickly, safely and to a number you can defend across Gladstone, Curtis Island and Central Queensland, ISS delivers survey-grade drone volumetric surveys flown under a CASA ReOC and reduced by licensed surveyors. Tell us your targets, accuracy and reporting cadence, and we will scope the right payload and return a fixed-price quote. Call 0407 057 015 or request a quote to get started.

Industrial Spatial Solutions — every cubic metre measured, every tonne defensible, from Port Curtis to the Bowen Basin.

Related reading: Gladstone industrial survey services, drone volumetric survey method, UAV aerial surveys overview.