Chevron operates and holds a 51.7 percent interest in the Frade project offshore Brazil. The field lies in water depths of about 1,128 m (3,700 feet), about 370 km (230 miles) northeast of Río de Janeiro, in the Campos Basin.
November 2011 Incident
On Nov. 7, 2011, Chevron Brasil Upstream Frade Ltd. was drilling an appraisal well in the Frade oil field, about 120 km (75 miles) offshore Brazil, when the well experienced an unanticipated pressure spike. As a result, steps were immediately taken to close in and secure the well. All subsea and surface equipment, including the blowout preventer, functioned as designed.
One day later, neighboring deepwater facilities southeast of the well reported a sheen of oil on the water. Although the wellhead was tightly sealed, further investigation found the presence of oil seeping through the sea bed at distances of more than 30 m (98 feet) from the wellhead.
Based on information we have to date, fluid escaped from the reservoir to reach thin fissures and migrated to the ocean floor. When these fissures were detected, an emergency response plan was immediately implemented and resources were dispatched to manage the situation. Steps were concurrently taken to contain and clean up the surface sheen, with as many as 18 vessels working in shifts around the clock on sheen remediation and well abandonment activities.
Response efforts were successful and the source of the leak was stopped in four days. However, residual droplets of oil have continued to migrate from the formation. Chevron continues to put containment devices in place to capture this oil.
March 2012 Incident
On March 14, 2012, Chevron Brasil Upstream Frade Ltd. identified a second small seep source and limited sheen while surveying the Frade Field. Upon discovery, regulatory agencies were immediately informed and containment devices were deployed to collect the small, infrequent droplets. The sheen had a volume of less than 1 liter (0.26 gallons) and extends over a distance of 1 km (0.62 miles). Chevron will continue to deploy these containment devices until all oil is captured.
Chevron Brasil has suspended production at the Frade Field as a precautionary measure after receiving approval from the National Petroleum Agency. At this time, all exploration and development drilling, with the exception of well abandonment activities, has been suspended.
Chevron Brasil Upstream Frade Ltd. has coordinated with Brazilian authorities at all stages and will continue to work with them until the incidents are fully resolved. Chevron is analyzing all data to understand the cause of the incidents and is working in cooperation with the appropriate authorities.