Conoco Phillips fined for oil spill

3 December 2009

On July 17, 2007, the site’s operator SGS (UK) reported that unleaded petrol was leaking from a storage tank at the Mayflower Terminal beside the Plym estuary. Tests revealed the fuel had leaked outside the terminal and contaminated adjoining premises. Nearby ground was ‘saturated’ and smelt strongly of petrol.

The incident was classed as ‘critical’ by the Police and Fire Service after they arrived at the terminal and were told the size of the spill. On July 25, 2007, the site was closed by the Health and Safety Executive (HSE) after petrol vapour was detected in the terminal control room.

The leak was traced to a hole in the base of one of the main storage tanks. A significant amount of petrol seeped into the ground beneath the tank. Approximately 36,000l of spilled fuel was recovered from the terminal and neighbouring premises by a specialist contractor brought in by Conoco Phillips.

The same contractor constructed a series of trial pits and boreholes that showed the ground beneath the terminal was heavily contaminated with fuel. Petrol was also detected in a limestone aquifer immediately beneath the site.

The Conoco Phillips terminals at Mayflower and Cattedown Wharf handle between 56-60 million litres of fuel a month. Petrol, diesel, gasoil and kerosene arrives by ship and is stored at the terminals before distribution. The Mayflower site lies within a former limestone quarry.

Magistrates heard that in addition to the pollution, the incident raised concerns for public safety because of the risk of fire or explosion.

‘This was a major spill involving tens of thousands of litres of fuel that had a serious impact on groundwater and the surrounding environment. The site will have to undergo costly monitoring for some time to track the spread of pollution in the underlying bedrock and groundwater,’ said Sarah Taylor for the Environment Agency.

‘This type of pollution incident is avoidable. Terminal owners and operators must ensure storage tanks and other equipment are regularly checked and maintained and, in the event of a spill, all the correct procedures are followed so as to minimise any impact on the environment. It also makes business sense because it avoids expensive pollution clean-up operations and monitoring after the event,’ said Sarah Taylor.

Conoco Phillips was fined £16,000 and ordered to pay £3,373 costs by Plymouth magistrates after pleading guilty to causing unleaded petrol to enter controlled waters at the Mayflower Terminal. SGS (UK) was fined £20,000 and ordered to pay £5,000 costs for the same offence.