An NBC2 Investigation examined the fragile future of deep sea shipwrecks which some have called "ticking time bombs."
They are relics of the past but posing potential problems for the future.
One ship in particular sits 75 miles from Southwest Florida and is now on the dederal government's radar. It's an oil cargo ship named the Joseph M. Cudahy, which could cause a mess for the environment and for tourism.
Records show the Cudahy had nearly 80,000 barrels of oil on board when a German U-boat blasted it with a torpedo during World War II.
Even though the ship sank in 1942, divers say oil still leaks into the water.
In 2010, Congress allocated $1-million for the National Oceanic Atmospheric Administration (NOAA) to form a database of shipwrecks and assess their threat.
It's called "Remediation of Underwater Legacy Environmental Threats – referred to as "RULET."
We were was given advance results of the assessment ahead of the national report coming out later this month.
Out of 20,000 ship wrecks off the coast of the U.S., NOAA determined about one hundred pose a substantial pollution threat.
Fewer, only six, are considered high priority for a most-probable discharge of oil. One of those ships is the Cudahy.
It's a ship Michael Barnette, from the Association of Underwater Explorers, knows well.
"One of the easiest ways to find the wreck when you're in the vicinity, especially on a calm day - you'll see a slick on the water," said Barnette. "You actually smell it before you get there."
Barnette is a respected diver who has written three books on Florida shipwrecks. He is a marine biologist who spends his free-time exploring underwater.
"There are still plenty of wrecks to be found," added Barnette.
The St. Pete native has identified or helped identify more than 50 shipwrecks worldwide, including the Cudyhy six years ago.
He said what makes diving intriguing is "piecing together in your mind what happened."