Does Offshore Oil Drilling Reduce Pollution?

Christine O'Donnell, who is challenging Joe Biden, repeats a number of the standard fossil fuel industry talking points in her op-ed advocating offshore drilling that appeared in the News Journal today. But the piece contained a point that I had not seen before:

Biden would like us to believe that offshore drilling is an environmental catastrophe. But only 1 percent of the oil pollution in the sea is the result of oil drilling, while 63 percent is the result of natural seepage on the ocean floor.

So the earth itself is messier than oil companies. Where did Ms. O'Donnell learn such startling truths? From the Free Republic perhaps? This excited post links to a 1999 press release from the University of California, Santa Barbara:

Next time you step on a glob of tar on a beach in Santa Barbara County, you can thank the oil companies that it isn't a bigger glob.

So what's forming these unsightly globs? The same press release tells us:

Most of the seepage is methane, a potent greenhouse gas which escapes into the atmosphere, said Luyendyk. About 10 percent of the seepage is composed of "higher hydrocarbons," or reactive organic gases which interact with tailpipe emissions and sunlight, creating air pollution.

Last I checked, methane doesn't end up on the beach in unsightly black clumps that stick to your feet.
It gets better. There are those who maintain that drilling offshore reduces pollution, arguing that we should drill it before it leaks. I tracked the assertion to the Institute for Energy Research, which published a report advocating exploitation of offshore oil reserves. This report included a citation to a study published by the National Academy of Sciences.
It turns out the study was funded, and even reviewed for content, by organizations like ChevronTexaco, Shell Global Solutions, ExxonMobil and the International Association of Independent Tanker Operators (INTERTANKO).
The UCSB press release concludes by saying that the rate of increase of global methane atmospheric concentrations has been declining for the past 20 years, and that a "worldwide decrease in natural hydrocarbon seepage related to onshore and offshore oil production may be causing a global reduction in natural methane emission rates."
In other words, oil companies have been reducing methane emissions without so much as a thank you from an ungrateful nation, though the researchers did not attempt to confirm this assertion. Also left unexamined is the question of how burning the methane instead of letting it seep into the atmosphere benefits the environment.
I imagine Ms. O'Donnell didn't delve too deeply into questions like these. She probably just saw a neat argument on a website and ran with it. She didn't say whether we should be drilling for oil off of Rehoboth, so we may never get the chance to test the hypothesis that offshore oil rigs reduce pollution here in Delaware. Of course, if you like the idea, you could always vote Republican and let us know how it works out.