“Deeply troubling” diesel leak threatens Bass Strait ecosystem

Fossil fuel multinational likely to breach environmental law again the offshore petroleum regulator has found after a 21,000 litre diesel leak on an offshore facility in the Bass Strait.

Jan96- Esso offshore drilling operation in Bass Strait. /mining-oil

The offshore petroleum regulator has warned of a potential significant environmental threat from an offshore oil and methane gas platform in the Bass Strait.

It was found a manual valve was left open for almost a day resulting in 21,000 litres of diesel leaking into its open pile storage system and some into the ocean.

Esso Australia Resources Pty Ltd, an affiliate of ExxonMobil, was found to have breached a provision of an environmental management law preventing spills in the environment and was likely to contravene that provision again by the National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA) at its Marlin B gas production facility in the Bass Strait, offshore from Victoria.

Esso offshore drilling operation in Bass Strait pictured in 1996. File picture

NOPSEMA issued an environmental improvement notice to Esso on September 12 after it was notified of the leak and found hydrocarbons had been released into the environment when a manual valve was left open while diesel was being transferred from a main storage tank to a day tank.

The notice said Esso personnel observed an oil sheen on the north side of the platform after an operator found the valve in the open position and closed it.

An Esso spokesman said there were no observed impacts to the environment and the “sheen dissipated quickly”.

NOPSEMA found there was — or was likely to be — a significant threat causing lethal or sublethal effects to marine fauna resulting from the leak.

Sub-lethal effects include disruptions to feeding or breeding behaviour and eye and skin irritations, the environmental improvement notice said.

Esso's Marlin B facility in the Bass Strait (low res) Picture: supplied

Greens spokesman for healthy oceans Tasmanian Senator Peter Whish-Wilson said Esso’s inability to manage its operational infrastructure was “deeply troubling”.

“Fossil fuel corporations make millions from Australia’s offshore oil and gas fields yet repeatedly breach our environmental management laws and have also gotten away with not properly cleaning up after themselves,” he said.

On Tuesday an Esso spokesman said the released diesel was largely contained within the facilities, however, “there was a very minor release of diesel”.

During the inspection a NOPSEMA inspector saw that Esso had failed to rectify known defects which resulted in the overfilling, and control systems in place had failed to prevent overfilling resulting in the hydrocarbons being released into the environment.

The NOPSEMA inspector said Esso was likely to contravene the environmental regulation again because the company failed to rectify known defects which resulted in the spill.

The Esso spokesman said they were “already executing changes which will ensure this does not happen again” and addressing NOPSEMA’s concerns.

“Esso prides itself on operating its offshore platforms in a safe and environmentally responsible manner,” he said.

Originally published as “Deeply troubling” diesel leak threatens Bass Strait ecosystem