State concludes mud spill investigation

Alaska DEC: BP should have reported releases, even though they did not present imminent or substantial risk to environment

Kristen Nelson

Petroleum News Editor-in-Chief

The Alaska Department of Environmental Conservation said March 25 that it has completed its investigation of a complaint it received that BP Exploration (Alaska) failed to report spills from one of its North Slope drilling operations.

In March 2003, the department said, BP and the department entered into a compliance reporting agreement requiring BP to report the release of low-risk substances including drilling muds to low sensitivity receiving environments, such as gravel pads. The department said that agreement includes a requirement to report the release of drilling muds in excess of 55 gallons, even when there is no release to the environment, a requirement that “is intended to alert both BP and the state so that steps can be taken to prevent future occurrences.”

The department said its investigation confirmed that no one from BP or their drilling contractor reported drilling mud releases which occurred July 31, 2003, and Dec. 5, 2004, when Nabors Alaska Drilling Rig 9ES experienced an event referred to as wellbore breathing. Approximately 294 gallons of mud were released within the walls of the drill rig.

The department said the releases did not present an imminent or substantial danger to the environment.

Leslie Pearson, program manager for the department’s prevention and emergency response program, said in a statement: “The state and BP have agreed that certain low-risk spills will be reported based on the quantity released so that problems can be assessed as they occur and corrective actions can be taken to prevent future spills.”

Department wants releases reported

Pearson said it is important that BP notify the department “even when they have a release that is confined to the drill rig with little if any harm to the environment.” The reporting, she said, allows the department to work with BP “to learn what went wrong and prevent more serious spills from happening.”

Daren Beaudo, BP Exploration (Alaska) director of public affairs, told Petroleum News in an e-mail that the Department of Environmental Conservation investigation “concludes, as does BP’s own internal investigation,” that the two releases of drilling mud from a Nabors rig were not a threat to public health or the environment, and occurred within the drill rig, which constitutes secondary containment.

Beaudo said most of the department’s report “is identical to the conclusions reached by BP.” He said BP expects to reach an understanding with the department regarding the agency’s “expectations of reporting requirements for this and other low-risk substances when they are confined to containment.”

Both investigations, Beaudo said, “concluded that drilling mud may have gotten on the outside walls of the rig but was properly cleaned up.”

The compliance agreement between the department and BP was signed by Pearson and BP’s environmental manager. The department’s report said the spills were not reported to BP’s Health, Safety and Environment staff. BP’s HSE personnel, the department said, “are responsible for assessing the information and ensuring compliance with reporting requirements.”