Drone Mining Survey Services in India

Geocartis carries out drone surveys of mining leases across India, built around the annual submission that Rule 34A of the MCDR 2017 requires. We fly the lease and the 100 metre buffer, establish and re-occupy permanent ground control, and deliver the full Indian Bureau of Mines package: orthomosaic and digital elevation models as GeoTIFF, the land use polygon shapefile, GCP and boundary pillar coordinates, the RMSE report and the survey log sheet. Capture is at 5 cm ground sample distance or better, which is what the IBM Standard Operating Procedure specifies.

We are based in Ahmedabad and mobilise to mining districts nationally. We are a survey and geospatial services company. We do not build drones and we do not sell software.

What Rule 34A actually requires

The Mineral Conservation and Development Rules 2017 were amended in 2021 to insert Rule 34A. It changed the mining survey from something a lessee did for internal planning into a dated statutory submission. Most of the confusion we encounter on site comes from lessees who know a drone survey is required but have not read the sub-rules, so it is worth setting them out plainly.

Sub-rule (1), the annual survey. Every lessee with an annual excavation plan of one million tonnes or more, or a leased area of 50 hectares or more, must carry out a drone survey of the leased area plus 100 metres outside the lease boundary, in the month of April or May, every year. The processed digital elevation model and orthomosaic go to the Controller General, Indian Bureau of Mines, on or before 1 July of the same year.

Sub-rule (2), everyone else. Lessees below both thresholds submit high resolution georeferenced orthorectified satellite imagery of the lease plus the same 100 metre buffer, captured between April and June, by the same 1 July deadline. Resolution 1.12 metres or better, cloud free, in GeoTIFF with metadata.

Sub-rule (3), the mining plan trigger. Any lessee submitting a mining plan document or a modification to IBM must have carried out a drone survey of the lease and the buffer within the preceding six months, and must submit the DEM and orthomosaic with the application. This applies regardless of tonnage or lease area. If you already filed under sub-rule (1) on the 1 July immediately before, you are not asked to repeat it.

Sub-rule (4), preferred bidders. Anyone issued a letter of intent for a mining lease through auction must survey the block plus the 100 metre buffer and submit the outputs alongside the mining plan.

Sub-rule (3) is the one that catches people out. A lessee with a 30 hectare lease and modest production assumes Rule 34A does not apply, then submits a mining plan modification and discovers a drone survey should have been done six months earlier. If a plan modification is anywhere on your horizon, the survey needs planning around it.

The IBM specification, in detail

IBM issued a Standard Operating Procedure under sub-rule (5) setting out how the survey is carried out and what form the data takes. It is prescriptive, and submissions get returned for falling short of it. This is the specification we work to.

Sensor and resolution

The camera must be RGB, minimum 20 megapixels, capable of capturing at less than 5 centimetres ground sample distance. Flying height is subject to DGCA limits, but the image resolution has to reach 5 cm GSD or better regardless. The camera points nadir, vertically downwards at 90 degrees.

Flight geometry

Forward overlap minimum 80 percent. Lateral overlap minimum 70 percent. The flight path plan and the number of flights used to cover the area are submitted to IBM with the data, so the plan is a deliverable and not just an internal working document.

Survey extent

The whole lease, including pits, dumps, stockyards, plant and infrastructure, plus 100 metres beyond the boundary so that environmental impact and any excavation outside the lease can be assessed. Where a lease shares a boundary with another lease, the survey can stop at the shared boundary on that side.

Ground control

At least five GCPs per square kilometre of lease area or part thereof, established with a calibrated or certified DGPS instrument. Minimum four GCPs where the area is under one square kilometre. At least three of the GCPs must be permanent, placed in undisturbed locations, and re-covered in subsequent surveys so error in change detection can be cross-checked. Individual GCP error must be under 5 centimetres. Markers are minimum 50 by 50 centimetres, drawn as an X in high contrast colours. Lease boundary pillars do not count as permanent GCPs.

IBM gives its own worked example: a 478 hectare lease needs 24 GCPs including the three permanent ones. Where part of the lease is under thick canopy and GCPs cannot be established, the count is reduced proportionately and the remaining points are redistributed across the accessible area. IBM’s example again: 200 hectares of a 478 hectare lease under canopy leaves 14 GCPs including three permanent ones across the remaining 278 hectares.

Coordinate reference system

Capture in Geographic Coordinate System on WGS84 datum, units in decimal degrees or degrees, minutes and seconds. The orthomosaic is submitted in UTM WGS84 with units in metres. GCP survey data and boundary pillar coordinates go in both forms, and the geographic precision format is specified down to six decimal places of arc seconds.

Timing

IBM recommends flying in good light with the sun overhead to minimise shadow, and avoiding partly cloudy days and high wind. On a deep pit with a high wall this is not a nicety. Shadow filling a bench face produces a point cloud hole exactly where the volume calculation needs data.

Data retention

The lessee keeps raw and processed data in safe custody for a minimum of five years and produces it if IBM asks for verification. Our contracts are written so that this obligation can actually be met, with the raw imagery handed over rather than retained by us as leverage.

How we do it

The sequence below is what a Rule 34A survey looks like from our side. It is the same shape for a 40 hectare limestone quarry in Saurashtra and a 900 hectare iron ore lease in Keonjhar.

Step 1: Documents before mobilisation

Before anything is planned we ask for the lease deed boundary pillar coordinates, the approved mining plan, the previous year’s survey if one exists, the mine code and the IBM registration number under Rule 45, and the annual return figures for the preceding year.

The boundary pillar coordinates matter more than clients expect. Annexure I to the SOP requires them, and they have to reconcile with the lease deed rather than with what somebody remembers being pointed out on site. Where the pillar coordinates in the deed disagree with what a GPS reads at the pillar, that discrepancy needs resolving before the survey rather than being discovered when IBM queries the submission.

The annual return figures matter because Annexure I asks for proposed excavation as per the mining plan and actual excavation as per the annual return, alongside your survey data. Those three numbers are read together. If the drone volumetrics disagree with the return, you want to know that in May and not in August.

Step 2: Ground control design and DGPS survey

We compute the GCP requirement from the lease area, then design the layout for coverage rather than convenience: points near every boundary, points at elevation extremes, points inside the pit as well as on the plateau. Control clustered in the middle of a lease produces error that grows towards the edge, which on a mining lease is precisely where the questions get asked.

Three permanent points go in first, at undisturbed locations chosen for a ten year horizon rather than this season’s mine plan. On an active mine that means away from the advancing face, away from dump toe lines and away from anywhere a haul road might be realigned. These are the points every future survey ties to, so their placement is the single decision with the longest consequences.

All points are surveyed with a calibrated DGPS. Alongside them we set independent checkpoints, surveyed to the same standard and deliberately withheld from the bundle adjustment, which is how we measure the accuracy of the block rather than assert it.

Step 3: Airspace and DGCA permissions

Registration with IBM is not required to carry out a mine survey, but everything DGCA requires applies in full. We check the site on the Digital Sky airspace map before quoting. Green zone leases can be flown up to 120 metres above ground level without prior flight permission. Yellow zone leases need permission from the relevant authority and carry a lower ceiling, which changes flight time and image count. Red zone leases cannot be flown at all, and IBM’s own rules acknowledge this by allowing an alternate mechanism where drone use is restricted by law.

Our aircraft carry active Unique Identification Numbers and our pilots hold DGCA Remote Pilot Certificates. Annexure I asks for the remote pilot licence number, the drone UIN, the aircraft category and the aircraft type, so these are submission fields rather than credentials nobody checks.

Step 4: Flight planning over pit topography

Ground sample distance is pixel pitch multiplied by flying height, divided by focal length. A 20 megapixel one-inch sensor with 5472 pixels across a 13.2 millimetre width has a pixel pitch of about 2.41 micrometres. Paired with an 8.8 millimetre lens and flown at the 120 metre green zone ceiling, that gives roughly 3.3 centimetres GSD, inside the 5 centimetre requirement with margin.

Mining leases complicate that arithmetic in a way flat sites do not. A pit with a 60 metre difference between crest and floor, flown at constant altitude above the take-off point, produces around 3 cm GSD at the crest and 5 cm at the floor. Add a 30 metre overburden dump and the dump top is finer still. We plan against an existing elevation model with terrain following so GSD stays inside specification across the whole lease, and we split the block into altitude bands where the relief is severe enough to need it.

Deep pits also need attention to flight line orientation. Nadir-only imagery reconstructs a near-vertical highwall poorly, because the wall is barely visible in a vertically pointed camera. Where bench geometry or highwall condition is part of what you need, we add oblique passes around the pit rim.

Step 5: Capture

Flying is scheduled around the middle of the day for sun angle, and around mine operations for safety and data quality. Blasting windows, shift changes and active haulage all affect when we can be in the air, and a lease full of moving tipper trucks produces ghosting in the mosaic. On most sites we agree a capture window with the mine manager rather than assuming free access.

Dust is the constraint nobody plans for. A dry lease with active haulage in May can put enough dust in the air to degrade a whole block. Where that is a risk we schedule early or negotiate a haulage pause across the critical strips.

The crew keeps a flight log covering flight numbers, heights, timings, battery cycles, GCP occupation and any anomaly. That log is submitted to IBM as the survey log sheet, so it is written properly at the time rather than reconstructed afterwards.

Step 6: Processing

Aerial triangulation runs first: tie point extraction across the overlapping images, then a bundle adjustment solving camera positions, orientations and interior calibration against the surveyed GCPs. Lens distortion calibration matters here, because an uncorrected model produces doming, and doming across a pit surface directly corrupts the volume figures that the whole submission rests on.

Dense matching generates the point cloud. Classification then separates ground from vegetation, plant, buildings, vehicles and infrastructure, which is what produces the difference between the DSM and the DTM.

Mining leases are the hardest classification case we deal with, and automated results always need checking. An overburden dump has the geometry of a natural hill and gets classified as ground by most automatic filters, which is correct for a DSM and wrong if you then treat the DTM as pre-mining topography. Mineral stockpiles have the same problem. Terraced benches confuse slope-based filters. Reclaimed and afforested areas sit somewhere between the two. We classify these by hand against the mining plan rather than accepting whatever the software produced.

Step 7: Land use classification

The SOP requires a single polygon shapefile in UTM WGS84 carrying the land use classification for the preceding financial year, with feature names in the attribute table. The classes are specified: lease boundary, actual excavation of mineral and waste, mineral storage, sub-grade stack, overburden and waste dump, afforestation, backfilled and reclaimed and rehabilitated area, topsoil stack, infrastructure such as workshop and mine office, roads, railways, tailing pond, effluent treatment plant, mineral separation plant, township, and any other feature including green belt.

This is manual interpretation work against the orthomosaic, cross-referenced to the mining plan and verified on site where the imagery is ambiguous. A topsoil stack and a sub-grade stack look similar from directly above. So do a partially reclaimed dump and an active one. Getting this layer wrong is one of the more common reasons a submission generates queries, because IBM reads it against your approved plan.

Step 8: Volumetrics and reconciliation

We compute excavated volumes, dump volumes and stockpile quantities from the surfaces, and we state the base surface method explicitly in every report: whether the base is the previous epoch surface, a surveyed hard standing, or a triangulated boundary plane. Two providers can produce materially different volumes from identical point clouds by choosing different base surfaces, and the number means nothing without that declaration.

We then set the survey figures alongside the proposed excavation from the mining plan and the actual excavation from your annual return, because Annexure I asks for all three. Where they diverge we tell you the size of the gap and what in the data explains it. Density assumptions, bulking factors, stock adjustments and survey date differences all produce legitimate variance, and having the explanation ready is better than being asked for it.

Step 9: Quality control and pack assembly

Residuals are computed at the withheld checkpoints and root mean square error is reported separately in horizontal and vertical. The RMSE report states the GCPs used, the checkpoints held back, individual residuals, aggregate figures, processing parameters and software.

The submission pack is then assembled to the SOP structure: orthomosaic GeoTIFF, DSM and DTM GeoTIFF, GCP data in Excel in both coordinate systems, permanent GCP data separately, GCP plan as a point shapefile, RMSE report, land use polygon shapefile, boundary pillar coordinates in Excel, boundary pillar plan as two separate point shapefiles for geographic and projected, the flight path plan, and the survey log sheet. Annexure I is filled from the survey record with every field completed.

You receive a pack ready to go onto a drive and be submitted, not a folder of files you have to work out how to assemble.

Accuracy and what 5 cm GSD means

Ground sample distance and accuracy are different quantities, and mining submissions get argued over when they are treated as the same thing. GSD is the ground area one pixel covers. Accuracy is how close a measured coordinate is to the truth. A block can have 3 cm GSD and 40 cm error if the ground control was thin or badly placed.

For a well-controlled photogrammetric block, horizontal RMSE typically lands between one and two times the GSD, and vertical RMSE between two and three times. At 5 cm GSD that suggests roughly 5 to 10 centimetres horizontal and 10 to 15 centimetres vertical. Those are expectations. The figures that go in the report come from the checkpoint residuals on your lease.

Vertical accuracy is the number that matters most on a mine, because volume is the product of area and height difference. A systematic 15 centimetre vertical bias across a 20 hectare pit floor represents 30,000 cubic metres of apparent material that is not there. This is why we hold back checkpoints, why permanent GCPs get re-occupied every cycle, and why we report vertical RMSE separately rather than quoting a single combined figure.

Two conditions degrade results on mining leases specifically. Dense canopy on the buffer strip or on unworked parts of the lease prevents the ground being seen, so the DTM there is interpolation, and we mark those areas rather than presenting them as measured. Water in the pit bottom generates no reliable tie points and appears as noise or a hole, so standing water needs either pumping before the survey or explicit exclusion from the volume boundary.

Deliverables and output file formats

The table below covers the statutory pack plus the outputs mines commonly add to it.

Raw imagery is handed over as part of the deliverable so you can meet the five year retention requirement without depending on us to hold it.

What mines use the data for between submissions

Treating the annual survey as a compliance cost is the most expensive way to buy one. The same dataset supports work that most mines otherwise pay for separately.

Production reconciliation. Monthly or quarterly flights over the working area give measured excavation volumes against declared production. On a lease where truck counts and weighbridge figures disagree, the surveyed surface is the arbiter.

Stockyard and stock accounting. Mineral storage, sub-grade stacks and product stockpiles measured from the point cloud rather than estimated from a tape and a cone formula. Irregular piles with craters and re-handled material are exactly where manual methods break down.

Dump stability and slope geometry. Overburden dump slope angles, berm widths and toe positions measured across the whole dump rather than at a few section lines. Repeat surveys show movement.

Haul road design and condition. Gradients, widths, camber and drainage measured off the surface model, which supports both cost and safety cases.

Boundary and encroachment. The 100 metre buffer is a compliance requirement, and it is also the answer to whether excavation has crossed the boundary. The Mining Surveillance System, developed by IBM with BISAG in Gandhinagar, screens for unauthorised activity within 500 metres of lease boundaries using satellite imagery. A current, accurate drone survey with pillar coordinates verified against the deed is the evidence you would want if a trigger is ever raised against your lease.

Reclamation and mine closure. Progressive mine closure plans commit to backfilling, reclamation and afforestation areas. The land use layer measures what has actually been achieved, year on year, from the same control.

Star rating and Sustainable Development Framework evidence. The IBM star rating scheme assesses leases against SDF criteria on a self-certified template validated by IBM. Measured areas for afforestation, reclamation, green belt and topsoil management are stronger evidence than declared ones.

Where we work

We are based in Ahmedabad and mobilise nationally. Mining work is concentrated in a handful of belts and we travel to them rather than expecting them to come to us.

Gujarat. Limestone across Saurashtra and Kutch, including the Porbandar, Ranavav, Jamnagar and Bhuj areas. Lignite in Kutch, Bhavnagar and the Tadkeshwar and Rajpardi fields. Bauxite in Devbhumi Dwarka, Jamnagar and Kutch. China clay, silica sand and dolomite across Sabarkantha, Panchmahal and Chhota Udepur. Ahmedabad, Gandhinagar, Rajkot and Bhavnagar are our usual staging points.

Odisha. Iron ore and manganese in Keonjhar, Barbil, Joda and Sundargarh. Coal and bauxite around Angul, Talcher and Jharsuguda. Bhubaneswar and Rourkela for access.

Chhattisgarh. Coal in Korba, Raigarh and the Hasdeo belt, iron ore around Bailadila and Dantewada, limestone across the Raipur and Baloda Bazar area. Raipur and Bilaspur for access.

Jharkhand. Coal in Dhanbad, Bokaro and Ramgarh, iron ore around Noamundi and Chaibasa. Ranchi and Jamshedpur for access.

Madhya Pradesh. Coal at Singrauli, limestone across Katni, Satna and Damoh, and diamond and other leases in the Panna area. Bhopal, Jabalpur and Indore for access.

Rajasthan. Marble in Rajsamand, Kishangarh and Makrana, zinc and lead around Udaipur and Bhilwara, limestone in Nagaur, Chittorgarh and Jaisalmer, and sandstone across Jodhpur and Bharatpur. Jaipur and Udaipur for access.

Karnataka and Andhra Pradesh. Iron ore in Ballari, Hospet and Sandur, limestone in Chitradurga, Gulbarga, Kadapa and Kurnool. Bengaluru, Hyderabad and Visakhapatnam for access.

Maharashtra and Telangana. Coal in Chandrapur, Wardha and Ramagundam, limestone and manganese around Nagpur and Gadchiroli. Nagpur is also where IBM headquarters sits, which matters for submissions.

Tamil Nadu, Kerala and Goa. Lignite at Neyveli, magnesite and bauxite around Salem, laterite and iron in Goa, and mineral sand along the coast. Chennai, Coimbatore, Kochi and Panaji for access.

North and north-east. Limestone and coal in Meghalaya and Assam, and the Himalayan limestone belt in Himachal Pradesh and Uttarakhand. Guwahati, Chandigarh and Dehradun for access.

What we do not do

A drone agency is not a mine surveyor, and any provider who blurs that line is creating a problem for you rather than solving one.

The statutory plans and sections under the Coal Mines Regulations 2017 and the Metalliferous Mines Regulations 1961 are the responsibility of a surveyor holding the relevant certificate of competency, appointed at the mine. Our data feeds those plans. It does not replace the appointed surveyor or their signature, and the DGMS framework does not permit it to.

Underground workings are outside what aerial photogrammetry can reach. Correlation surveys between surface and underground remain a ground survey exercise.

Photogrammetry does not see through canopy. On leases with substantial forest cover, particularly in the Odisha and Chhattisgarh belts, the ground surface under the canopy is interpolated. Where the buffer strip or unworked lease area is heavily wooded and the levels matter, LiDAR is the correct sensor and we will say so rather than delivering an interpolated surface and calling it a DTM.

Red zone leases cannot be flown by anyone commercially. IBM’s own rules provide for an alternate mechanism precisely because of this.

Timing the annual survey

April and May is a narrow window, and it is narrow for the whole industry at once. Capture in April or May, submit by 1 July, which leaves a processing and review period that looks generous until you account for a reflight.

Our recommended sequence puts ground control establishment in February or March, well before the capture window, because permanent GCPs need to be set, marked and surveyed and that is a separate mobilisation. Capture then happens in the first half of the window rather than the last week of May, which leaves room to refly if weather, dust or a control problem forces it. Processing, land use interpretation and pack assembly run through June with time for you to review the volume figures against your annual return before submission.

Leaving the whole exercise to late May means a single bad weather week removes your ability to comply. Monsoon onset in western and central India makes June an unreliable fallback.

Frequently asked questions

Which mines must do a drone survey under Rule 34A?

Any lessee with an annual excavation plan of one million tonnes or more, or a leased area of 50 hectares or more. Separately, any lessee submitting a mining plan or a modification must have surveyed within the preceding six months regardless of size, and preferred bidders with a letter of intent must survey the auctioned block.

What is the deadline?

Capture in April or May, submission to the Controller General, Indian Bureau of Mines on or before 1 July of the same year.

What resolution does IBM require?

Less than 5 centimetres ground sample distance, from an RGB camera of 20 megapixels or more. The orthomosaic is submitted at 5 cm resolution or better, and the DSM and DTM at 15 cm or better, all in UTM WGS84.

How many ground control points does my lease need?

Five per square kilometre or part thereof, with a minimum of four if the lease is under one square kilometre, and at least three of them permanent. A 478 hectare lease needs 24, which is IBM’s own worked example. Where thick canopy prevents establishment, the count reduces proportionately across the accessible area.

What if my lease is under the thresholds?

You submit high resolution georeferenced orthorectified satellite imagery instead, at 1.12 metre resolution or better, captured April to June, by the same 1 July deadline. You still need three permanent GCPs established with DGPS, with markers sized at 2.5 times the image resolution so they are identifiable.

Do I need to register the drone agency with IBM?

No. IBM does not require registration of the drone agency. DGCA requirements apply in full, and the agency details, pilot licence number and drone UIN are recorded in the submission annexure.

Can we do the survey ourselves?

The SOP permits the lessee to carry out the survey directly, provided all DGCA rules and guidelines are followed. In practice the constraints are the DGPS control work, the classification and interpretation, and the pack assembly, which is where most in-house attempts run into difficulty.

What file formats do you deliver?

Orthomosaic as GeoTIFF and JPEG. DSM and DTM as GeoTIFF. Land use, GCP plans and boundary pillar plans as shapefiles. GCP and pillar coordinates as Excel. RMSE report, log sheet and Annexure I as PDF. Contours as DXF and SHP. Point cloud as LAS and LAZ. Object marking as DXF and TIFF. Sections and overlays as DXF, DWG and PDF.

How long does a lease survey take?

Capture on a typical lease is one to three days depending on area, relief and airspace, with ground control establishment as a separate earlier visit. Processing and pack assembly follow, and we agree the delivery date at proposal stage against your submission deadline.

Can you compare this year against last year?

Yes, provided the permanent GCPs from the earlier survey are still in place and identifiable. That is why the SOP requires three permanent points covered in subsequent surveys. Where the previous survey used a different provider we can usually tie into their control if the coordinates and marker positions were properly recorded.

Do you handle DGCA permissions?

Yes. We check the airspace classification when quoting and obtain the permissions the site requires.

Get a quote for your lease

Send us the lease area in hectares, the boundary as a KML or shapefile, the mineral, the state and district, and whether you are filing under sub-rule (1) or triggered by a mining plan submission. We will come back with the GCP requirement, the flight plan, the delivery schedule and a fixed price.

If your submission is due this 1 July, the control work should be starting now rather than in April.