The bulk of the oil is found in deltaic sands of Eocene Mirador and the Upper Cretaceous formation.
The produced crude oil is transported by the Caño Limón – Coveñas pipeline to Colombia's Caribbean coastline.
The National Institute of Renewable Natural Resources and Environment repeatedly criticized the operation.
Later in 1992, it conducted water sampling studies that found high concentrations of heavy metals and polycyclic aromatic hydrocarbons.
It found that "because of the polluting effluents from Caño Limón, the receiving rivers and lakes are no longer fit for human consumption.