Under the sea: Fighting Greece's plastic trash problem

Dressed all in black and preparing his diving gear with loud zips and clicks, George Sarelakos looks like he's part of a Greek naval operation ready to storm an island or take down smugglers. He's not - but he and four other volunteer divers do have a challenging mission: Clearing the plastic trash from the sea floor that's suffocating Greece's marine life.

In a heavy rain, they struggle to clamber off the rocks along a stretch of coast south of Athens favored by day-trippers looking for a nice place to swim within driving distance of the Greek capital.

"Most beaches are clean because they're tidied up by municipalities. But the big problem is on the seabed. It is like a garbage dump," Sarelakos said.

In January, the European Union launched a major campaign to reduce plastic waste across its 28 member states. Greece starts the 12-year program with major...