Jet fuel in the North Sea ‘not going to persist’ after collision

On Monday, a cargo ship en route to the port of Rotterdam in the Netherlands crashed into a US military-chartered oil tanker anchored in the North Sea off the British coast. The Stena Immaculate was carrying roughly 50 million L of jet fuel.

The force of the collision resulted in jet fuel being released and “multiple explosions onboard,” according to a statement by the logistics firm Crowley, which manages the tanker. The cargo ship Solong also caught fire, and both crews had to abandon ship, with one crew member missing and presumed dead.

The volume of jet fuel released is still unclear, although a March 11 update by Crowley says that “initial review shows impacts have been limited due to exposure to the fire and evaporation of the Jet A1 fuel.”

In an email to C&EN, Mark A. Sephton, professor of organic geochemistry at Imperial College London, says that jet fuel, with hydrocarbon chains made of 16 carbon atoms or fewer, is volatile and will easily evaporate, something that many chemists will have experience with. “As a rule in the lab, we lose <C18 if we leave the lid off a vial containing an organic extract,” he says.

Some of the hydrocarbons can dissolve in water, which would potentially expose animals that might be living in the water, says Christopher M. Reddy, a chemist and oil spill researcher at Woods Hole Oceanographic Institution.

But jet fuel’s volatility and flammability are an aid in this disaster. “It’s not going to persist,” he says. “Jet fuel release is a short-lived event because, for the most part, most of those components are going to evaporate and are going to be diluted by mixing with air, and then eventually they'll get broken down by reactions from sunlight.”

History provides a couple of lessons. In January 2018, the Iranian oil tanker Sanchi was carrying condensate oil, which is similar to jet fuel in volatility, when it collided with a cargo ship, creating one of the world’s largest oil spills in history. Given the nonpersistent nature of the oil, “it resulted in significantly lower environmental impacts compared to some crude oil spills,” according to International Tanker Owners Pollution Federation Limited.

Burning also helps reduce potential injury to humans and marine life. Five of the top 10 oil spills in history were fire-related, Reddy says, and the general consensus from those 5 spills was the fire kept the disaster from getting worse.

In a statement on March 12, Virginia McVea, chief executive of the UK's Maritime and Coastguard Agency, confirmed that “there have been no further reports of pollution to the sea from either vessel beyond what was observed during the initial incident. HM Coastguard’s counter pollution and salvage team has a comprehensive counter pollution response in place should it be required. Salvors also have equipment and personnel ready to respond to any pollution."

The environmental impact of the spill has yet to be determined, but in addition to degrading chemically, small-chain hydrocarbons are likely to be broken down by bacteria in the seawater. The degradation rates of different hydrocarbons are well known because of the economic impact of biodegradation on oil quality, Sephton says.

Other variables such as the location and temperature of the spill will play a role, as will any other compounds involved and their volume. “There will also be lots of partial combustion products that may be a problem (they were in the smoke), but the impact depends on the amount of material being generated,” he says.

Current air-quality sampling onshore and modeling from UK agencies suggest that there is no threat to the public.

Reddy says it is crucial to remember that each oil spill is different. And location plays a big role in eventual impact not only in terms of whether the spill is in threatened areas but also in terms of capacity to respond. "Folks in the UK and all around the North Sea are incredibly talented and really strong oil spill responders,” he says. “If there’s something that they can do that is going to [keep] this bad thing from getting worse, they're going to do it.”