Russian tanker leaking oil off Oman coast, threatening environmental disaster

A Russian tanker carrying millions of gallons of oil has run aground off the coast of Oman — and now risks breaking apart, potentially causing an environmental disaster on the scale of the 1989 Exxon Valdez spill .

The Caroline Bezengi, which has been linked to Russia's so-called shadow fleet to move sanctioned oil around the world, was damaged by an unexplained explosion on June 8. The tanker had departed Russia, traveled through the Suez Canal and entered the Gulf of Oman when its crew abandoned ship, according to John Amos, whose environmental nonprofit SkyTruth has been tracking the ship for weeks. Left adrift, it eventually grounded on a rocky outcropping near a small, uninhabited island.

Satellite images showed the first signs of an oil leak on June 30, Amos said. He estimates that hundreds of thousands of gallons had spilled by Aug. 7. Five of the tanker's six cargo holds were filled with oil, Amos said, meaning the vessel could have been carrying as much as 40 million gallons.

The ship's owner has given no public indication that it is responding to the accident, and the tanker may not have adequate insurance. That has left Oman with responsibility for containing the spill and preventing a far larger disaster. The government has deployed aircraft, divers and specialized personnel to assess the vessel and prepare mitigation efforts, according to Greenpeace.

Ambrey , a British maritime security and salvage company, says crews are on their way to the tanker. But they will face what the company described as "extreme adverse weather and sea conditions influencing vessel stability" as monsoon storms batter the region.

Safely removing the remaining oil will require a complex operation, and according to Hanen Keskes, regional campaigns lead at Greenpeace MENA, the full extent of the leak may not be known until that work is completed.

The environmental stakes are considerable. The Gulf of Oman and the Arabian Sea are home to protected marine life, including sea turtles, sharks and a rare population of humpback whales. The waters surrounding the grounded tanker were also recently designated a marine reserve.

Russia relies on hundreds of aging tankers in its shadow fleet. The vessels often operate through opaque ownership structures and may carry little or no credible insurance, raising questions about who will ultimately pay for the salvage operation and environmental cleanup.

Amos warns that even a rapid response can recover only a fraction of the oil released into the sea.

"Once the oil hits the water, you've already lost," he said, estimating that spill-response efforts typically recover only about 20%.

The potential cost is enormous. Exxon spent approximately $2.1 billion after at least 11 million gallons of oil spilled from Exxon Valdez off Alaska's coast in 1989 — roughly $5.8 billion in today's dollars.