Read this article by Stephen Hume in the Vancouver Sun. "Something is exceptional when it happens so infrequently that when it does occur, it's a surprise.
"But I know from my reporting career, which was ushered in by a series of massive pipeline spills in Alberta more than 40 years ago, that these events occur with depressing regularity.
"The pipeline industry has had almost half a century to work on the problem, yet oil spills, explosions, fires and toxic pollution as a consequence of ruptures are anything but exceptional. They still happen on an almost daily basis."