Vergessene Wracks 2017 ( 7.6)

There are ticking time bombs off the coasts of the world, of which the public has hardly been aware: 6,300 wrecks, sunk during the Second World War, have been rusting in the sea for more than 70 years. Researchers estimate the amount of oil remaining in them at up to 15 million tons. What can be done to prevent an oil slick?