C-DRONE GUIDE · 16 SEPTEMBER 2026
Contaminated Land and Drones: ICPE Decommissioning, Remediation Earthworks, Price
More than 11,000 sites are now listed in BASOL, France's inventory of contaminated or potentially contaminated sites requiring public-authority action, and more than 300,000 in CASIAS, the record of former industrial and service-activity sites. For an operator closing a classified installation, those figures translate into a concrete procedure: since the reform took effect on 1 June 2022, it must produce a rehabilitation memorandum documenting the safety measures and, depending on the chosen use, the site's remediation, under the oversight of a certified consultancy rather than the classified-installations inspectorate alone. On a remediation site that often runs for several months — earthworks, temporary stockpiling of excavated soil, containment works — a drone provides a precise service: measuring volumes, dating progress, documenting the state of the works, without ever replacing the boreholes and laboratory analyses that alone characterise pollution. Here is how these two worlds fit together, and the prices observed in 2026.
Published on 16 September 2026, reviewed on 16 September 2026 — regulations in force as of September 2026.
ICPE decommissioning since 2022: the rehabilitation memorandum and certified consultancies
Decree No. 2021-1096 of 19 August 2021, effective since 1 June 2022, reformed the decommissioning procedure for France's classified industrial installations (ICPE). When the site's future use is already set in the prefectural operating permit, the operator has six months after final shutdown to submit a rehabilitation memorandum — which replaced the former decommissioning memorandum — detailing the safety measures and, where the chosen use requires it, the remediation works. Absent a timely decision from the prefect or a submitted memorandum, the default retained use stays comparable to that of the last operating period.
Another notable change under the reform: part of the oversight now shifts to certified consultancies specialised in contaminated land, who attest that safety and rehabilitation works comply, alongside the classified-installations inspectorate. It is this same type of consultancy that commissions and interprets the drone surveys discussed below: the aerial mission fits into a chain of responsibilities where each party — operator, consultancy, prefecture — keeps its own role. For sites headed toward land redevelopment rather than agricultural or natural restoration, our guide on drone brownfield mapping covers the next steps once decommissioning is settled.
What a drone survey measures on a remediation site: earthwork volumes, progress, containment works
A remediation site moves earth: excavating contaminated soil, temporarily stockpiling it before treatment or disposal, backfilling once treated. At every stage, the consultancy and the project owner face the same question: how many cubic metres were excavated, how many remain stockpiled, does the volume shipped out match the waste tracking form? A drone topographic survey, repeated before and after each phase, answers through photogrammetry: a digital surface model compared between campaigns gives the moved volume, without ground surveying in an area sometimes off-limits for health reasons — the same principle as earthwork volume calculation in quarries and civil works, applied here to soil whose handling is tightly regulated.
A study by Paulina Raeva, Silvia Filipova and Dobromir Filipov, published in 2016 in the International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, compared a classic GNSS survey of a material stockpile against its drone photogrammetry reconstruction at an open-pit quarry: the two methods converged, validating drone use as a reliable alternative for this kind of earthwork volume calculation (see the study on Google Scholar). A broader review by Anette Eltner and co-authors, published in 2016 in Earth Surface Dynamics, details the reliability conditions of drone photogrammetry for reconstructing a ground surface: density of ground control points, image overlap, texture of the photographed surface (see the study on Google Scholar) — conditions a serious contractor respects so that a remediation site's earthwork figures hold up under scrutiny.
Beyond volumes, the dated orthophoto documents site progress for the project owner and its insurer, and oblique photos check the state of containment works: waterproof tarps over stockpiles awaiting treatment, geomembranes, retention berms — equipment whose tear or settling can go unnoticed at ground level but stands out clearly from above.
The central honesty point: a drone never characterises soil pollution
However precise, a drone survey remains a survey of geometry: areas, volumes, elevations, the visual state of structures. It measures neither the nature nor the concentration of pollutants in the soil or groundwater — that remains the work of boreholes, piezometers and laboratory analyses carried out by a consultancy certified in contaminated land. Interpreting the state of the environment, defining a management plan and setting remediation thresholds suited to the chosen use call for geochemical expertise that a camera, thermal or multispectral, does not provide here: unlike a crop's water stress or a roof leak, soil contamination leaves no reliable visual or thermal signature at the surface.
Nor does the drone remove the need for the case's own administrative steps: checking the soil information sectors (SIS), created by the ALUR law of 24 March 2014 and available on Géorisques, filing the rehabilitation memorandum, financial guarantees where the installation is subject to them. Its role is precise and limited: giving the consultancy and the operator dated, verifiable geometric data — an earthworks quantity survey, proof of progress, the state of containment works — that support a regulatory case file, never replace it.
Who commissions this survey, method and 2026 prices
This kind of mission first serves industrial operators going through an ICPE decommissioning, often supported by a contaminated-land consultancy that commissions the surveys and keeps their interpretation. It also serves developers and public land agencies acquiring a potentially polluted site for redevelopment, and local authorities that own or border a site under remediation and track its progress for their own information or planning needs.
The most robust method combines a baseline flight before works, one or more intermediate flights at key stages (end of excavation, before backfilling) and a final as-built flight, each producing a digital surface model georeferenced with ground control points — the same methodological standard as a drone topographic survey or a standard construction site monitoring mission. On a long site, these flights naturally slot in between the consultancy's own sampling campaigns, without replacing them.
Ranges observed in France in 2026, excluding VAT:
| Service | Observed price (excl. VAT) |
|---|---|
| Baseline flight before works (orthophoto + DSM, up to 5 ha) | €700 to €1,300 |
| Intermediate earthwork survey (end of excavation or stockpiling) | €500 to €1,000 per visit |
| Full periodic monitoring (3 to 5 visits over a multi-month site) | €2,000 to €4,000 |
| Final as-built flight (progress evidence for the case file) | €600 to €1,200 |
Against the sums involved in remediating a site — often several hundred thousand euros — this monitoring is a marginal share of the budget, while securing the quantity surveys that support the rehabilitation memorandum. The regulatory information on this page reflects the rules in force in September 2026. Request a quote stating the site's area, the site's progress and the planned schedule.