We're past the one-year anniversary of the BP (NYSE: BP) oil spill but it has become apparent that BP isn't the only one leaching oil into the environment. In just the last two months there have been a number of smaller oil spills that have managed to stay out of the public eye.

In March, more than 800 tons of fuel leaked from an oil ship into a remote portion of the South Atlantic coating thousands of endangered penguins.

Last month Kinder Morgan Energy Partners (NYSE: KMP)/Kinder Morgan Management (NYSE: KMR) shut down its Trans Mountain oil pipeline after a leak was discovered. The company said that a "small amount of product seep was found in a farmer's field west of Edmonton." The company excavated the pipe and a sleeve has been applied to fix the leak.

The hole in the pipe was described as a "pinhole," which makes me think they must make much bigger pins in Alberta than they do in Minnesota. If a farmer was able to notice the oil, it must have been a fairly significant amount.

Then earlier this month a Plains All American Pipeline (NYSE: PAA) spilled 28,000 barrels of oil in Alberta because repairs made in 2010 didn't hold up. Customer Penn West Petroleum (NYSE: PWE) has been forced to find alternative means of transportation for its oil.

The sad thing is this isn't even a comprehensive list of oil spills from pipelines in North America over the last year. I guess big spills like the BP disaster and Exxon (NYSE: XOM) Valdez are the only ones that get press -- even though smaller spills are a regular occurrence.

Externalities of oil
These are the kind of externalities to the environment we rarely consider when talking about oil consumption. But they're very real and occur far more often than you might think.

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