Detecting Illegal Mining with Sentinel-2: A Guide for West African Regulators

Illegal and unregulated mining scars land, destroys farmland and poisons rivers. Ghana's galamsey crisis has turned major rivers brown, and Nigeria has seen deadly lead poisoning linked to artisanal gold mining in Zamfara. Inspectors can't be everywhere, but satellites revisit every few days.

What gives mining away - New bare-soil patches in forests or farmland. - Pits and ponds with distinctive shapes and colours. - River turbidity spikes downstream of active sites. - Access tracks appearing in remote areas.

The detection pipeline 1. Build cloud-free composites from Sentinel-2 every week or fortnight. 2. Run change detection and an AI classifier trained on known mining sites. 3. Score river segments for turbidity to trace pollution to its source. 4. Push alerts with coordinates to enforcement teams. 5. Verify in the field and feed results back into the model.

Beyond enforcement - Licensing authorities can check that operators stay within concession boundaries. - Water utilities can anticipate treatment challenges. - Communities and journalists can access evidence.

StrikeClimate builds mining-watch dashboards for regulators, utilities and environmental agencies.