Bulgaria Disputes Oil Slick Claims Near Sanctioned Tanker Wreck

A Damaged Tanker, a Disputed Slick

Bulgarian authorities are pushing back against claims that a persistent oil slick near the Black Sea coast originates from the hulk of the sanctioned crude tanker Kairos. According to a report by The Maritime Executive, the 150,000 dwt vessel has been anchored in Burgas Bay since December 2025, after suffering severe damage in a Ukrainian drone attack north of Turkey in late November 2025.

The strike sparked a major fire that wrecked the bridge and accommodation block and left the engine room partially flooded. Turkish authorities helped evacuate the crew before the tanker was taken under tow. Days later, it ran aground in Bulgarian waters, with claims that the towing tug had effectively abandoned the vessel there. It took roughly ten days before Bulgaria could move the wreck to a safer anchorage in Burgas Bay.

Conflicting Assessments

Concerns about pollution resurfaced last week when the Nessebar Public Council, representing a tourist-heavy stretch of coastline about 20 nautical miles from the wreck, called on the government to act. In response, Bulgaria’s Transport Ministry and Maritime Administration carried out inspections within a 1.5-nautical-mile radius of the tanker on July 22. Officials reported finding no active slick, though they did note scattered discolored patches that were treated with dispersant. A hull inspection reportedly turned up no signs of active leakage.

Greenpeace Bulgaria has reached a different conclusion. Using Sentinel-1, Sentinel-2, and PlanetScope satellite imagery, the environmental group says it traced slick activity back to an image from April 26, 2026, with further sightings recorded in mid-May and again on July 21. Greenpeace estimates the affected area stretches roughly 6.5 nautical miles and says the recurring pattern visible in both radar and optical imagery is consistent with petroleum products near the vessel. Greenpeace Bulgaria coordinator Martin Tomov stated the group has high confidence the stains are oil-based, while acknowledging that chemical sampling and an on-site inspection would be needed to confirm the source definitively.

Ownership Complications

The Kairos, built in 2002 and flagged to Gambia, was reportedly owned by a Chinese company before being sanctioned by the European Union in May 2025 and the United Kingdom in July 2025, both citing its repeated links to the Russian oil trade. Bulgaria’s Transport Ministry says it remains in contact with the Chinese owners, who have since informed authorities that the vessel has been sold to a cash buyer intending to scrap the hulk in Turkey.

What It Means for Owners and Inspectors

This dispute highlights a recurring problem with damaged or sanctioned tonnage left in limbo: once a vessel becomes a stranded hulk, responsibility for monitoring its condition often becomes murky, spread across flag administration, coastal state, and a changing chain of ownership. The gap between Bulgaria’s near-shore visual inspections and Greenpeace’s satellite-based tracking over several months illustrates why remote sensing alone, or a handful of localized checks alone, may not settle the question. For ship managers and charterers dealing with vessels involved in casualties, sanctions listings, or prolonged lay-up, this case is a reminder that independent condition surveys — including hull and tank integrity checks conducted by parties without a stake in the outcome — remain essential wherever a wreck or hulk sits near sensitive coastlines. Sale to a scrap buyer does not resolve the underlying question of whether the hull is still discharging oil, and until a proper on-site technical inspection with sampling takes place, the discrepancy between official statements and satellite evidence is likely to persist.

For now, Bulgaria says it will continue monitoring the site, while Greenpeace is calling for a fuller, independently verified investigation into the tanker’s condition.

Reviewed by Ibrahim Halil Ceylan, Marine Surveyor at Apeks Marine.