Last week, a new patch of oil popped up on the surface of the Gulf of Mexico. Everyone was like, “Gee, I wonder if that’s from the BP spill,” all sarcastically. BP was all, “Woah woah, guys, the jury’s out! Let’s just wait and see! Maybe there’s a new type of fish that is turning into oil spontaneously or something. Our scientists say it’s possible!” And the scientists were like, “Yeah, that’s possible,” as they were depositing their big paychecks. (This thing about the oil fish is just a joke, I guess I should point out.)

Even small incidents like this can have a lasting consequence.

Anyway, the oil was from the Deepwater Horizon spill, surprising no one. From the Washington Post:

The oil in a slick detected in the Gulf of Mexico last month matched oil from the Deepwater Horizon spill two years ago, the Coast Guard said Wednesday night, ending one mystery and creating another.

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“The exact source of the oil is unclear at this time but could be residual oil associated with the wreckage or debris left on the seabed from the Deepwater Horizon incident,” the Coast Guard said.

The Coast Guard added that “the sheen is not feasible to recover and does not pose a risk to the shoreline.” One government expert said the thin sheen, just microns thick, was 3 miles by 300 yards on Wednesday.

Some oil drilling experts said it was unlikely that BP’s Macondo well, which suffered a blowout on April 20, 2010, was leaking again given the extra precautions taken when it was finally sealed after spilling nearly 5 million barrels of crude into the gulf.

Right. And BP’s anti-spill precautions have a sterling track record.

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One theory is that the oil came from the pipe that once ran from the well to the surface, which now lies broken on the floor of the Gulf. The U.S. Geological Survey estimates that the riser, as the pipe is known, could hold as much as 1,000 barrels of oil. Each time some leaks out, we’ll get to play this fun “Where could it be from?!” game again.