Race on to prevent oil slick disaster Pollution experts in bid to save coastline

Oil spillage: Birds and mammals at risk as inquiries begin into how Liberian tanker ran aground off Wales

NICK SCHOON

Environment Correspondent

A 20-mile stretch along some of Britain's most prized coastline has been polluted by crude oil from the stricken tanker Sea Empress, it became clear last night.

Over half the estimated 1,000 tons of oil spilt from the tanker has already come ashore along the Pembrokeshire coast, in and outside the huge natural harbour of Milford Haven in west Wales.

This weekend the battle is on to prevent a bigger spillage and an even greater disaster. For the 140,000 ton Liberian-registered supertanker, which ran aground on Thursday night, was trapped less than half a mile from a rocky shore with gale force winds forecast.

The supertanker has sunk lower in the water after losing oil from tanks ruptured when she hit rocks at the mouth of Milford Haven. A list of 10 degrees was adding to the problem. She had a draft of nearly 80 feet and was just 10 foot off the bottom at low tide.

Today, salvagers were hoping to bring another much smaller and shallower tanker, the Star Bergen, alongside. This vessel would take 30,000 of oil off the Sea Empress, reducing her draft to the point where she could safely be brought into harbour without risk of grounding again.

Four tugs were hurrying towards the super tanker late last night to help keep her in position as the weather worsened. But Michael Hislop, general manager of the Milford Haven Port Authority, said: "We can live with these winds.''

Yesterday, a Dakota aircraft hired by the Department of Transport's Marine Pollution Control Unit sprayed oil dispersant on the slick of North Sea crude. But it failed to take effect because the oil had already turned into a "mousse" - a thick mixture of tiny oil droplets and water.

Oil came ashore between St Ann's Head and St Govans's Head, a stretch of coastline entirely within the Pembrokeshire National Park. Crude oil is also slicking the shores of Milford Haven, a deep water estuary with three giant oil refineries and important feeding grounds for wading birds.

But there were few reports of oiled birds on the beaches last night. The fresh north-westerly wind blew the oil away from the islets of Skokholm and Skomer, two of the most important sea bird breeding grounds in Britain.

Hundreds of staff from the local council, Texaco - owner of the refinery to which the Sea Empress was heading - and the oil industry's Oil Spill Response Centre were mopping up on beaches yesterday. The clean up should last several more days, but many of the oiled coves are impossible to reach because they are at the bottom of 150ft cliffs.

The ship's owners yesterday ruled out steering or engine failure as the cause of the incident, but navigational error seems a possibility. There was a pilot on board at the time.

The incident has renewed calls for new tankers to be built with double hulls, although the Sea Empress is only three years old and was built to regulation safety standards at the time.

Last October, the supertanker Borga ran aground in similar circumstances, but a spill was averted because it had a double hull. In his report on the Braer oil spillage in the Shetland Isles, Lord Donaldson agreed that double hulls could avert some leaks.