Last year’s tsunami in Japan threw 1.5 million tons of debris into the ocean. It’s starting to show up on the West Coast — a soccer ball here, a motorcycle there, a 66-foot, 165-ton dock. According to the Associated Press, more might be coming. Or it might not. But when the debris arrives, if enough arrives, it could be dangerous enough to be a national emergency.

No one knows for sure what’s going to happen next. The AP talked to “some experts” who thought most of that debris would chill out in the ocean, far from American shores. But they also talked to experts with names, like Chris Pallister, who was not so sanguine:

“I think this is far worse than any oil spill that we’ve ever faced on the West Coast or any other environmental disaster we’ve faced on the West Coast” in terms of the debris’ weight, type and geographic scope, said Chris Pallister, president of a group dedicated to cleaning marine debris from the Alaska coastline.

Part of the worry is that the debris that washes up won’t be innocuous, poignant debris like soccer balls. Instead, states could be dealing with barrels full of unknown chemicals. (And yes, according to the federal government, it’s the states that will be dealing with it.) But if the debris is coming, it’s probably not coming until fall, when storms stir up the oceans. So, West Coasters, get your beach time in now! Better safe than sorry.

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