Divers in Florida have started work at the bottom of the sea, to clear up an environmental mess made by people more than 40 years ago.
In 1972, authorities dropped 700,000 old car tyres into the sea.
Back then environmental experts thought that dumping them in the ocean would be good for fish and other sea life by creating an artificial reef for them to live in.
It also provided a handy solution the fact that rubber tyres couldn't be recycled in those days.
But the plan didn't work out. The tyres were washed across more of the ocean floor by currents and storms and started to damage the natural sea life rather than help it.
Now the authorities in Florida say they are committed to removing as many of the tyres as possible and have re-started a plan from 2007 to spend $2 million (£1.29 million) dollars doing it.
Although it only took one day for all the tyres to be dumped back in 1972, clearing them up will take years.
Divers will have to work 70 feet under water, hooking bundles of tyres onto a crane, which will then hoists them onto the barge.
Once the tyres have been lifted, they will be burned to generate energy, but they expect that half a million will still be left at the bottom of the sea. Divers in Florida have started work at the bottom of the sea, to clear up an environmental mess made by people more than 40 years ago.