Environmental Risk Assessment for Offshore E&P Activities in Brazil

Abstract

Brazil has performed an important role in the oil and gas industry mainly because the offshore E&P activities in Campos Basin, characterized by deep waters far away from the coast and its sensitive areas. However other basins have increased their importance in the E&P industry where some operations are located very close to the shore in shallow waters with a remarkable environmental sensitivity. Because of this, a new approach has been adopted by Brazilian Federal Environmental Agency (IBAMA) - firstly regarding oil spill preparedness and lately concerning environmental risk assessment. Risk analysis used to be developed as a preliminary hazard analysis (PHA) part of the environmental impact statement that operators (oil companies) have to perform in order to obtain a permit to operate. The main feature of this PHA was the qualitative and subjective risk assessment taking into account only the oil spill amount, in spite of the area sensitivity. Once the operations in those high sensitivity areas have potentially increased, IBAMA has developed a particular Term of Reference regarding the oil spill risk calculation for valued environmental resources such as marine mammals, sea turtles, fishes, etc as well as ecosystems (for example, coral reefs and mangroves). According to the new approach the environmental risk assessment regards to the recovery time of any valued environmental resource that could be affected by oil spill in comparison with the leakage occurrence time. The oil spill risk related to a valued environmental resource is calculated by the product of the release frequency and the environmental consequences based on exposure probability. This paper discusses this new approach adopted in Brazil, involving a quantitative method for the environmental risk assessment of Brazilian Offshore E&P.