Petrobras, Brazil’s state-run energy giant, has formally opened South America’s largest-capacity natural-gas pipeline, the 179-kilometer Gasduc III, near Rio de Janeiro, which required tunneling 3.8 km through Santana Mountain. The 40-million-cu-m-per-day, 38-in.-dia pipeline was built by Odetech, a joint venture of Odebrecht and Techint Engenharia. It is the largest-dia gas pipeline in South America.The pipeline awaits the completion later this year of the Caraguatatuba-Taubaté (GASTAU) gas pipeline, which will receive gas coming from the Santos Basin in the Atlantic Ocean.