A HAMPSHIRE beach remained closed last night as investigations continued into the health and environmental impacts of the oil spill at Fawley refinery.

Oil spill experts were yesterday digging test holes between Hill Head and Meon Shore to determine whether the chemical had seeped below the surface.

If given the all-clear, Fareham Borough Council could declare the popular beach safe as early as this morning.

Wildlife experts, however, expressed fears about the long-term effects of the spill on the fish, plants and birds that inhabit the shoreline.

As a precaution, the Health Protection Agency has already closed shellfish beds off the Fareham coast.

The clean-up operation was set to continue into a third day after 20 barrels of vacuum gas oil spilled into Southampton Water on Sunday night.

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Refinery bosses Esso said the oil leaked from a pipeline as a ship was being unloaded at the company’s marine terminal.

Vacuum gas oil is carcinogenic – cancer-causing – however, an Esso spokesman said the oil that washed up was at a “very low concentration”.

Esso said the substance was similar to central heating oil. It is used at Fawley as the feed for the catalytic cracking unit in the production of petrol.

The petroleum giant said it represented a “very low risk to health”, but that some people may experience a mild skin irritation.

“Anyone who has come into contact with the oil can remove it using soap and water and, if they have further concerns, should contact their GP,” he said.

Booming at the entrance to Titchfield Haven Nature Reserve appears to have successfully stopped any oil reaching the site of special scientific interest (SSSI).

Natural England said they had received no reports of effects from the spill, such as oily birds or dead fish.

The main concern is for eelgrass and saltmarsh plants, which provide food for birds such as Brent geese and widgeon ducks.

The plants also provide an important breeding ground for cuttlefish and provide shelter for crabs, spire shell snails, periwinkles and lugworms.

Jolyon Chesworth, marine expert at the Hampshire and Isle of Wight Wildlife Trust, called for long-term monitoring of contamination.

“I don’t know the toxicity of the oil, but if it has been dumped on the eelgrass at low-tide it could have quite a significant impact,” he said.

Sacks of contaminated shingle were yesterday taken to the refinery, where they will be cleaned and assessed to see whether they can be returned to the shore. The environment Agency (EA), meanwhile, said it was investigating the cause of the spill and collecting evidence that could lead to a prosecution against Esso.

Dawn Theaker, from the EA, said: “Esso moved quickly to contain what they could, but some oil did wash up on the beach.We have seen no environmental impact from our observations.”

Fareham Borough Council leader Sean Woodward said the council had received no reports of people suffering ill effects and was hopeful Meon Shore would be reopened today.

Councillor Woodward also said he expected Esso to cover the cost of the clean-up operation.

The incident occurred just two days after the Daily Echo questioned whether a disaster on the scale of the Gulf of Mexico could ever happen in the Solent.

Southampton harbourmaster Phil Holliday was satisfied with the clean up operation, but said lessons would be learnt from the incident.