Even With a Cleanup, Spilled Oil Stays With Us

[Cees Binkhorst]

REPLY TO: D66 at nic.surfnet.nl

Volgens onderstaand artikel maakt BP zichzelf 'onsterfelijk en blijft ze
eeuwenlang onder ons.'
Dat is toch eigenlijk wat elke bestuurder wil?
Nu nog een gerechtelijke uitspraak, waardoor de kosten gelimiteerd
worden, en dan mogen 'we' er ook nog voor betalen.

Groet / Cees

Even With a Cleanup, Spilled Oil Stays With Us
By BILL MARSH
Published: June 5, 2010

BP, in a series of newspaper advertisements about the Deepwater Horizon
disaster, says it is “working around the clock to contain and collect
most of the leak” and it will “take full responsibility for cleaning up
the spill.”

But if past catastrophes are guides, the cleanup by BP workers will
capture only a fraction of the crude belched up by the broken well. Much
of the oil will be taken care of by nature; the rest is likely to stay
with us for decades.

In Alaskan coastal zones fouled by the Exxon Valdez in 1989, scientists
discovered oil, scarcely changed, 16 years later. In some areas, its
composition had not altered much from the toxic clumps and goo that had
formed just weeks after the spill.

Contrary to early expectations, oil still oozes from Alaska’s beaches,
toxins intact, and is expected to remain — perhaps even for centuries.

The BP disaster differs greatly from the Valdez. In the Gulf of Mexico,
vast plumes of oil, attacked with harsh chemical dispersants, churn up
from mile-deep waters. In Alaska, a surface slick swept over more than a
thousand miles of rocky coast. Spilled oil behaves in many ways, but
here, based on sad experience, is some of what to expect in the gulf.

How it Disappears:

EVAPORATION Some oil on the water surface evaporates within days. The
lighter the oil, the more evaporation: half or more of light crudes can
evaporate; medium crudes, up to 40 percent evaporate; heavy crudes as
low as 10 percent. The spilled oil in the gulf is light crude, according
to Edward B. Overton, an environmental sciences professor at Louisiana
State University; Exxon Valdez oil was heavier.

DISPERSAL Oil may be reduced to tiny droplets by wave action or
chemicals. Droplets are more readily consumed by microbes, but the
effects of toxic chemical dispersants used in the gulf are not known.

EATEN BY BACTERIA If conditions are right, microbes can consume a great
deal of spilled oil. But this is not always possible in oxygen-starved
environments, like the deep sea or where oil has seeped into beach
sediments.

REMOVAL Armies of workers at the Exxon Valdez disaster — 11,000 at the
effort's peak — removed less than half the oil that didn't evaporate or
biodegrade.


What Remains

OIL ‘MOUSSE’ Residual emulsified oil — a gooey mix of crude from the
Exxon disaster and water, remains in beaches in Alaska.

BURIED OIL Crude that penetrated into coastal sediments remains in
dismaying amounts in Alaska. When sand and rock is disturbed — by
burrowing or foraging animals, or surf — oil may leach out. Otherwise
the oil remains intact and resistant to degradation. Pictured above: oil
from a small hole dug on May 5 on Eleanor Island, Alaska.

TAR BALLS AND ASPHALT Congealed oil forms tar balls that resist
weathering and can last for years; mix sand or beach gravel with oil and
you get asphalt, which also resists erosion. Tar balls washed up on
Florida beaches in the early days of the gulf spill, but they were not
from Deepwater Horizon — they may have formed from other spills, or
occurred naturally from oil seeps in the ocean. Pictured above: a tar
ball in Pensacola, Fla. on Friday.

INTO THE FOOD CHAIN Oil and toxins concentrate in filtering animals like
mussels, oysters and clams and are then ingested by their predators. The
long-term effects of this are not fully understood, but oil ingestion is
known to damage animals’ immune systems and organs and cause behavioral
changes that affect the ability to find food or avoid predators.

SLOWED RATES OF OIL LOSS Most of the oil from the 1989 Valdez disaster
disappeared in the first few years. Scientists had hoped that almost all
the remaining oil would disappear soon after, based on how quickly the
oil was degrading in the early 1990s.

But later surveys showed that this oil was much slower to degrade,
leading scientists to fear that it may persist for decades. About 100
tons of oil was still in the beaches of Prince William Sound as of 2001,
out of more than 20,000 tons deposited there. And it is easily uncovered
there today.

Sources: Gail V. Irvine, U.S. Geological Survey; Lisa Suatoni, Natural
Resources Defense Council; Edward B. Overton, Louisiana State
University; Chris Reddy, Woods Hole Oceanographic Institution; United
States Fish and Wildlife Service; National Oceanic and Atmospheric
Administration; Exxon Valdez Oil Spill Trustee Council; Environmental
Science and Technology

------------------------------------
50% Biodegraded on beach or in water
20% Evaporated
14% Recovered or disposed
13% Remained lodged in sediments
  2% Remained on shores
<1% Remained in the sea
Above is what happened to the more than 40.000 tons of oil in the Exxon
Valdez disaster, according to a study conducted three years after the spill.

Related:
Gulf of Mexico Oil Spill Multimedia Collection
http://www.nytimes.com/interactive/us/spill_index.html?ref=weekinreview

* Political Times: Obama, the Oil Spill and the Chaos Perception (June
6, 2010)
http://www.nytimes.com/2010/06/06/weekinreview/06bai.html?ref=weekinreview

* Cap Slows Gulf Oil Leak as Engineers Move Cautiously (June 6, 2010)
http://www.nytimes.com/2010/06/06/us/06spill.html?ref=weekinreview

* Under the Waves, a Deep Unknown (May 30, 2010)
http://www.nytimes.com/2010/05/30/weekinreview/30broad.html?ref=weekinreview

* Times Topic: Gulf of Mexico Oil Spill (2010)
http://topics.nytimes.com/top/reference/timestopics/subjects/o/oil_spills/gulf_of_mexico_2010/index.html

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