Drilling mud spilled from rig east of St. John's

The board that regulates Newfoundland and Labrador's offshore oil industry says more than 26,000 litres of drilling mud spilled  from an oil rig operating east of St. John's on Monday.

The Henry Goodrich rig was drilling an exploration well for Suncor when the incident happened.

Canada-Newfoundland Labrador Petroleum Board spokesperson Sean Kelly described it as a significant spill.

"Heavy mud like that goes through the water column and ends up on the ocean floor," he said.

"It certainly it does have an impact on the environment that we consider serious. We need to continue with the investigation to find out what those impacts are."

Drilling mud is used in the industry to prevent oil or gas from escaping during drilling operations.

Studies have found that a common drilling mud additive, used as a thinner, can harm fish eggs and fry. Other mud additives have reported effects on marine organisms, including reduced fertility and higher mortality.

Kelly said Thursday that depending on the outcome of the investigation, there may be charges.

He said it appears the drilling mud was released from a valve on the rig that was left opened.

According to the C-NLOPB Monday's incident is the largest spill of drilling muds since 2007.

The board said 74,000 litres of drilling mud were spilled in the Orphan Basin area of the North Atlantic Ocean in January 2007.