Oyu Tolgoi Mine Biodiversity Offset — Net Positive Impact Programme (Mongolia)

Oyu Tolgoi is one of the world's largest copper-gold mines, operated by Rio Tinto's Oyu Tolgoi LLC in Ömnögovi Province in Mongolia's South Gobi Desert. As a condition of IFC and EBRD project financing under IFC Performance Standard 6, the operator committed in 2011 to a Net Positive Impact (NPI) on biodiversity, using a "Quality Hectares" metric that combines habitat area with a habitat-quality score to compare losses at the mine site against gains delivered through a landscape-scale offset.

The offset area spans roughly 80,000 km² of Gobi rangeland — about 880 times the size of the mine's own footprint — where Oyu Tolgoi funds anti-poaching patrols, measures to reduce road and rail barrier effects on wildlife migration, and rangeland-quality improvements, delivered with technical partners The Biodiversity Consultancy, The Nature Conservancy and Fauna & Flora International.

Since 2013, the Wildlife Conservation Society's Mongolia programme has run core biodiversity monitoring surveys tracking two flagship species: khulan (Asiatic wild ass) and goitered gazelle. The most recent counts found populations of roughly 36,000 khulan and 28,500 goitered gazelle, essentially stable over the monitoring period — genuine population-level field evidence rather than a modelled projection.

Independent Environmental and Social Consultant (IESC) audits commissioned under the lenders' agreement have repeatedly found Oyu Tolgoi in "substantive compliance" overall but have also flagged specific biodiversity non-conformances, prompting a revised Biodiversity Action Plan and the creation of an independent scientific advisory panel. No published, hectare-level reconciliation of losses versus gains under the Quality Hectares metric is publicly available, so whether the Net Positive Impact target itself has been met remains unverified.

Read the full analysis: https://measures.wcs.org/Metric-Details/m/12