The area covers my whole country and then some. Although small compared to whole Earth, I'm pretty sure you wouldn't enjoy having the spill as a next-door neighbour.
Good thing it's out in the sea, then.
Um, you can see it on the surface of the entire earth. How many other man-made things can you see at that scale?
At a small enough scale, even pretty small is pretty big.
If you consider the total human population of the Earth, a single murder is pretty insignificant. We probably should stop prosecuting people for murder...