The full scoop on those oil seeps

The full scoop on those oil seeps

By Deborah Brasket

Oil and gas have been seeping from the ocean floor into the sea for thousands of years, and the Santa Barbara Channel is home to one of the largest seep fields in the world.

This fact has been misused by some powerful interests, who would like to lift the offshore oil drilling ban. An industry-funded group called Stop Oil Seeps (SOS) is advocating for increased drilling off Santa Barbara’s coast, claiming this will reduce natural oil seeps harmful to the environment.

Two weeks ago, I wrote a column debunking some of the myths being used to support lifting the offshore oil ban, including this one. Since the question about oil seeps has aroused local interest, here are further details on the subject, examining two crucial questions: Does natural oil seepage harm the environment? If so, does offshore oil drilling help to reduce the seepage?

So, how harmful are oil seeps to the environment? We know seep vents release several gaseous and liquid hydrocarbons, and some are toxic. However, studies show most of these harmful elements dissolve or biodegrade rapidly in the water before ever reaching the atmosphere, while others become part of the food chain.

The parts that do make it to shore in the form of tar or pitch may be a nuisance, but have no significant effect on nearshore ecosystems, according to a definitive study published in the Journal of Geophysical Research. The harmful gases that do reach the surface contribute to only 5 percent of the smog in our county, according to the Santa Barbara County Air Pollution Control District.

The burning of fossil fuels is a far more significant factor in air pollution. Altogether, research indicates that the seeps are not a significant cause of air or water pollution in Santa Barbara County.

Given this reality, the question of whether oil drilling will reduce seeps may be a moot point. In any event, the research regarding this question is inconclusive. While one study indicates a decline of seepage near Platform Holly, there is insufficient evidence to support or refute the claim that oil drilling is actually the cause of reduced oil seepage.

Moreover, the reduction supposedly caused by drilling in one area could actually cause increased seepage in another area.

According to one local geohydrologist: “During a major cleanup operation at Cape Canaveral, the injection of steam into a contaminant source area spread the contaminated plume to areas that had previously been clean. As a result, cleanup estimates increased by more than five-fold.

“This exemplifies the fact that injection of materials to encourage movement and extraction of petroleum . . . is not always controllable.”

In the end, there’s no clear evidence that natural seepage does grave harm to the environment, or that drilling will reduce seeps rather than increasing seepage elsewhere. The argument that lifting the offshore oil ban will cure natural oil seepage is itself a red herring.

One critic responding to my last column wrote: “Was the SOS claim that drilling will stop seepage directed to a few specific fields, or all fields? Because it's a nonsensical claim. It has been shown to be the case in isolated instances. But the vast majority of oil fields have no seeps at all. And many fields that do have seeps are already being drilled. Anyone who knows the industry knows this . . . .listen to authoritative voices, not extremists.”

An intelligent debate on lifting the ban on offshore oil drilling should not be sidetracked into a discussion about oil seeps. I hope this column helps put that argument to rest.