Sunday, June 20, 2010

Of Seepage and Oil Spills

1. The Santa Barbara Channel with red dot to mark Summerland, site of the spill.

2. Closeup of the beach affected by the spill, from Coal Oil Point and UCSB at the north end of Goleta to Rincon Point, a surfers favorite and also the county line.

Today, most writers who bring up the 1969 SB oil spill in relation to the Gulf are hoping that today's spill will cause the same kind of political movement that happened then. Certainly when Tony Hayward said that the combination of low mud, a methane surge, and a concrete plug that didn't hold was "unprecedented" he was hoping no one remembered the circumstances of the Santa Barbara blowout.

1969 Oil Spill (click here to read the full account)
On the afternoon of January 29, 1969, an environmental nightmare began in Santa Barbara, California. A Union Oil Co. platform stationed six miles off the coast of Summerland suffered a blowout.

Oil workers had drilled a well down 3500 feet below the ocean floor. Riggers began to retrieve the pipe in order to replace a drill bit when the "mud" used to maintain pressure became dangerously low. A natural gas blowout occurred. An initial attempt to cap the hole was successful but led to a tremendous buildup of pressure. The expanding mass created five breaks in an east-west fault on the ocean floor, releasing oil and gas from deep beneath the earth.

For eleven days, oil workers struggled to cap the rupture. During that time, 200,000 gallons of crude oil bubbled to the surface and was spread into a 800 square mile slick by winds and swells. Incoming tides brought the thick tar to beaches from Rincon Point [about 8 miles south] to Goleta [27 miles north], marring 35 miles of coastline. Beaches with off-shore kelp forests were spared the worst as kelp fronds kept most of the tar from coming ashore. The slick also moved south, tarring Anacapa Island's Frenchy's Cove and beaches on Santa Cruz, Santa Rosa and San Miguel Islands.

Ecological Impact

Animals that depended on the sea were hard hit. Incoming tides brought the corpses of dead seals and dolphins. Oil had clogged the blowholes of the dolphins, causing massive lung hemorrhages. Animals that ingested the oil were poisoned. In the months that followed, gray whales migrating to their calving and breeding grounds in Baja California avoided the channel —their main route south.

The oil took its toll on the seabird population. Shorebirds like plovers, godwits and willets which feed on sand creatures fled the area. But diving birds which must get their nourishment from the waters themselves became soaked with tar. The survival rate was less than 30 percent for birds that were treated. Many more died on the beaches where they had formerly sought their livelihoods. In all 3686 birds were estimated to have died because of contact with oil. Aerial surveys a year later found only 200 grebes in an area that had previously drawn 4000 to 7000.

(This text was sourced to Silicon Beach Communications, which no longer has it posted.)

Question 1: How much of current seepage was caused by the blowout 40 years ago?

UCSB is on Coal Oil Point near the airport in Goleta. Coal Oil Point is so named because it has a long history (noted by the Chumash Indians) of natural seepage, particularly methane, from under the ocean floor.

By the early 1980s, the area's top three industries were banking, tourism, and fishing. Residual seepage was light enough that big tourist beaches like East Beach, where pro volleyball tournaments are now held, could be kept white and pristine. Kelp beds thrived in the channel, seafood was wholesome, and whales used the Channel for migration. Today Carpinteria, just south of the spill site, regularly ranks as one of the nation's cleanest beaches.

I attended UCSB from 1981-1983. The narrow beaches adjacent to the school were dotted with globs of tar on the rocks and had black silty sand woven in with the tan-colored sand. Most students had a pair of "beach shoes," that picked up tar from the beaches and were unfit for other use (mine were blue jute sandals). The place had some residual fuel smell, but the strongest smell came from the eucalyptus trees planted up and down the shore. The net effect was (and is) a nice smell, not a stench. There was some resentment that these beaches were not considered important enough to keep clean, but it wasn't the most important issue to most people.

In the early 1980s, the conventional wisdom was that there had been more seepage and more tar globs on the beaches since the oil incident, but I never heard of any actual data supporting or disproving this. This is one of several studies claiming positive impact of drilling. Its authors have both university and oil company credentials. Like most people, I don't have the background to judge the validity of geological findings.

MMS has minimal credibility, but I still point out a study from April 15 of this year on natural seepage that they helped to fund.

Question 2: How long will it take for the Gulf to recover to a point where it can a) sustain a full complement of aquatic life and b) provide human food?

The SB damage was so much less than the Gulf--200,000 gallons (wasn't that about what the Gulf got the first day?) floating over 800 square miles, somewhat contained within the channel by natural boundaries of shore and islands. Some birds and animals were able to avoid the damage, but the spill was contained after less than two weeks, and cleanup was quick. Despite this, rebuilding was still slow. For example, only a tiny fraction of grebes returned the following year. The Gulf seems to require multiplying all of these figures by about elebenty, a suitably vague number for damage that can't be totaled yet because it is still happening.

Question 3: Will the Gulf continue to have permanent seepage from under the ocean floor caused by damage from drilling? If so, Santa Barbara, with its permanent seepage and flourishing aquatic life, may be a useful model of how the Gulf may adapt to its new circumstances. At least it is a positive example of how seepage and aquatic life may coexist.

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