You may recall that back in February, 3,000 gallons of heavy fuel oil (HFO) spilled into the water off Shuyak Island, Alaska. The spill occurred when hurricane force winds destroyed an old fuel dock, releasing this tar-like substance into designated critical habitat for the endangered Northern sea otter and Steller sea lion.

Last week, the U.S. Coast Guard and Alaska Department of Environmental Conservation concluded their response efforts. Cleanup operations removed more than 1,800 bags of oiled absorbent material, but did not succeed in removing all the spilled oil.

Luckily, there have been no reports of oiled wildlife. However, both the cost of the cleanup and delay in response time tell a frightening tale. And, let’s not forget that HFO spills are much more difficult to respond to and much more detrimental to the marine environment than spills of marine distillate fuel.

The price tag to address this relatively small spill was shockingly high—$9 million dollars! According to the International Council for Clean Transportation, the global average HFO cleanup cost is around $24,000/ton; this cleanup was 33 times costlier! The delayed spill response time is also alarming. The spill occurred only 30 miles away from the nearest response site, and yet it took three days to get response vessels to the scene due to rough weather.

In many areas of Alaska—especially north of Shuyak in the Arctic—response vessels could be more than 1,000 miles away. Ice and rough weather would further complicate response efforts, and result in an even higher price tag. And this was a relatively small spill. An HFO spill in the Arctic would likely come from a large vessel that uses HFO as fuel. This sort of spill could be orders of magnitude larger than the Shuyak incident. For example, the 2004 Selendang Ayu incident off the Aleutian Islands released 350,000 US gallons of HFO and diesel into the environment, more than 100 times the volume of oil in the Shuyak spill.

The Shuyak incident shows us that even a relatively small spill of HFO is extremely costly, and that even in a relatively easy response scenario, not all oil can be recovered. Such a precautionary tale is one of many reasons Ocean Conservancy supports the ban on the use and carriage for use of HFO by ships in the Arctic. Let’s make sure something like this never happens in Arctic waters.