An environmental authorisation draws a line on a map: this is where you may disturb the ground, and no further. The breach of that line is rarely a decision — it's drift. Satellite monitoring through the build is the dated record that catches the drift while it is still cheap to fix, and proves compliance where the line held.
The breach is usually drift, not a decision
Almost nobody sets out to build outside their permitted footprint. What happens is quieter: a laydown yard spreads a little wider than planned, an access track is widened or a second one is cut for convenience, spoil and stockpiles are placed just over the boundary because it was the nearest flat ground, a turning circle creeps into a no-go buffer. Each step is small, made under time pressure by a subcontractor who never saw the authorisation. Added up across a solar field or tens of kilometres of line, they are exactly the excursions an environmental control officer is appointed to prevent — and the ones a developer gets held to afterwards.
Why a site visit can't be the whole record
Construction moves fast and covers ground that is hard to police from the seat of a bakkie. A linear route runs for kilometres; a renewable-energy site is hundreds of hectares. A monthly walkover is a sample: it sees where the inspector went, on the day they went, and misses the week a track was cut in the far corner and then partly rehabilitated before the next visit. Satellite imagery removes the sampling problem — it reads the whole footprint, on a schedule, every few days, measured the same way each time — so an excursion shows up as a dated change in the data rather than something someone has to happen to catch.
What the monitoring actually measures
The method is disciplined and narrow. Against the approved development footprint — the permitted boundary as a polygon — each period's imagery is read to map where ground was actually cleared or disturbed. The output is a dated series: disturbance extent per period, overlaid on the permitted line, with any excursion flagged, located and quantified in area. Because every period is measured against the same boundary in the same way, the record is comparable through the build and afterwards — a tamper-evident account of where and when the ground was opened.
It protects the developer too
This is usually framed as catching wrongdoing, but the same record is the developer's defence. When a lender's adviser or the authority asks whether construction stayed inside the line, a documented monitoring series answers yes, here is the evidence — for the majority of a site where compliance held — instead of an assurance that has to be taken on trust. Evidence cuts both ways, and most of the time it exonerates.
Where the line sits
The monitoring layer evidences where and when disturbance occurred relative to the approved footprint, with its uncertainty stated. Determining the consequences of any excursion — and any enforcement — rests with the authority and the appointed environmental control officer. TerraX produces the evidence they act on; it does not adjudicate the breach.
Catch the drift while it is a corrected track and not a finding in a compliance audit. That's what our construction compliance monitoring is built to do — tell us the project, the footprint and how often you need the record.