Deep in Lake Erie, near Kelleys Island Shoal, a sunken barge lies. It might be a ship called the Argo, which sank in a 1937 storm and was said to have been carrying about 100,000 gallons apiece of the tar-like benzol and crude light oil, according to the Toledo Blade.
A few years ago, the National Oceanographic and Atmospheric Administration (NOAA) included the Argo on a list of 89 shipwrecks thought to be significant threats to United States waters because of cargo or fueling systems.
The Argo is one of the five such vessels left behind in the Great Lakes.
Recently, following a "report of a discharge of an unknown substance," according to this press release, the Coast Guard went to the site but have not found the leak underwater.
Responders saw a spreading stain on the water. "What has been reported from responders is consistent with a lighter-end petroleum-based solvent that would quickly dissipate when it reaches the air," Lt. Cmdr. Anthony Migliorini, commanding officer of Marine Safety Unit Toledo, said in the Coast Guard news release.
Even so, it has not yet been determined that the Argo is the source of the leak. "We're 99.9 percent certain," Kowalczk said, according to the Washington Post.
At this point, the area has been separated from boat traffic and a salvage company plans to investigate and secure the leak later this week, the Blade reported.
"We're fairly certain there's a leak," Migliorini told AP. "It's really hard for us to point to a specific cause."
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