When Hurricane Katrina struck the Gulf Coast in August, no one was immune from its rage. The hurricane hit oil and gas infrastructure particularly hard. More than 100 platforms were destroyed or lost, major pipelines were shut down, and refineries and oil storage sites lost power and were flooded and heavily damaged. While thousands of people rushed out of the area, struggling to avoid rising flood waters, some folks were rushing in. They were hoping to prevent — or at least quickly clean up — what would become America’s largest oil spill since the 11-million-gallon Exxon Valdez spill in Alaska in 1989 (see sidebar, page 35 Print Exclusive).
The Katrina factor
Damage
to oil facilities from Hurricane Katrina caused four medium spills (more than
10,000 gallons) and 134 minor spills, in which 8 million gallons of oil leaked
onto the ground and into waterways from Louisiana to Alabama. The largest single
spill was at the Bass Enterprises Production Company site in Cox Bay, La., where
3.78 million gallons of oil spilled. Another large spill was at the Chevron
Empire oil terminal in Buras, La., where the roof of one storage tank was ripped
off and the foundation of another ripped out, leaking 1.4 million gallons of
oil.
At the Chevron Empire oil terminal in Buras, La., oil spill responders used
a controlled burn to clean up oil that spilled out of several of the facility’s
tanks following Hurricane Katrina. The storm caused at least 8 million gallons
of oil to leak at a number of different facilities, making it the second largest
U.S. oil spill. Image courtesy
of U.S. Coast Guard/Petty Officer 3rd Class Robert M. Reed.
Hundreds of workers responded to the spills within a day of the hurricane’s
strike, despite many having lost their homes, says Mickey Driver, a spokesman
for Chevron. “Besides ensuring the safety of our personnel, our first priority
was to respond to those spills,” he says.
And that’s true of all the energy companies in the area, Driver adds, despite
some “incredible logistical challenges,” such as no electricity, water,
food, sewage, fire department or emergency services, phone lines or other communication,
and no place for anyone to stay. “We had to keep flying in people daily
and housing others on barges,” he says.
Additionally, Marine Spill Response Corporation (MSRC), an industry-funded nonprofit
oil spill cleanup organization, brought in seven vessels (with 38 berths apiece)
designed for spill response that served as “command and control centers”
following Katrina, says Judith Norell, a spokesperson for the organization.
The ships served as sleeping and mess halls, logistical and staging support,
communications facilities and spill cleanup headquarters, she says. MSRC acts
sort of “like your local fire department, in that [the oil companies] fund
us, hoping they never have to call us, but we’re ready to provide spill-response
services if they need us,” Norell says. The organization responded to 32
individual incidents related to Katrina, which was one of the most challenging
cases that MSRC has faced, she says.
In addition to the logistical and communications challenges Katrina caused,
the storm also challenged responders by causing many different types of spills,
from the tank spills to capsized fishing boats, in many different environments,
from the Mississippi River to marshes to tank farms. “Our entire team was
deployed to multiple sites,” says Tom Callahan, deputy division chief of
the Hazardous Materials Response Division of the National Oceanic
and Atmospheric Administration (NOAA). “We haven’t had that many
people in the field since the Exxon Valdez.”
“A pretty key component” of the oil spill response team, Callahan
says, NOAA provides scientific expertise to the U.S. Coast
Guard and Environmental Protection Agency (EPA) during
an oil spill. Although many governmental agencies are involved in spill response,
EPA has oversight of any spills inland, and the Coast Guard oversees spills
in any coastal areas or “major navigable waterways.” In some cases,
such as Katrina, spills may involve both inland and coastal areas, in which
case both agencies may oversee the coordination of the response. Together, the
government agencies, alongside the responsible parties, local officials and
“cooperative” organizations such as MSRC, form a joint command to
figure out a course of action, says Jim Clark, head of ExxonMobil’s Oil
Spill Research Program.
The technology
Spill responders have a wealth of different technologies at their disposal to
deal with oil spills. Mechanical technologies, such as tools to contain the
oil, are the most widely used in the United States, but newer technologies,
such as chemicals that disperse the oil, are gaining ground, Clark says.
One cleanup tool is a mechanical boom, which is essentially a floating barrier
with a skirt, “kind of like curtains,” placed around a leaky tanker
or an oil slick, Callahan says. As oil floats on the water surface, a boom collects
it within the barrier. The oil can then be scooped up by tools such as skimmers
or absorbed using sorbents. Skimmers take oil off the water surface, much as
someone would skim the fat off gravy using a sieve. Sorbents, which can be natural
materials such as peat moss, straw or clay, or synthetic materials such as plastic,
soak up oil from the surface of the water.
“Alternative technologies” are also available “in the toolbox,”
Callahan says, including chemical dispersants that break down oil to distribute
it throughout the water column, biological agents (such as plants and bacteria)
that speed up the degradation rates, and in situ burning, which involves burning
the oil slick on the water surface to prevent its spread. Once oil hits a shoreline,
additional technologies can clean up the ground, such as pressure washing and
vacuuming or suctioning up oil.
Before the joint command decides what technology (or suite of technologies)
to employ at a site, Callahan says, “there are five things we need to know.”
The first is what type of oil has been spilled. Each type of oil has distinct
physical and chemical properties that affect the way it spreads and breaks down,
and the hazards it poses. For example, light refined products such as gasoline
and jet fuel are highly volatile so they naturally evaporate faster than crude
oils, but they’re also more toxic to the environment and pose a greater
fire hazard.
Secondly, the responders need to look at how much oil was spilled. The amount
spilled largely dictates the type of cleanup technology to be used. For example,
sorbents work very well to clean up small spills or remnants of spills, but
do not work as well on very large spills, where booms might be a better solution.
Next, responders need to figure out where the oil is going — its trajectory
and whether it will evaporate or disperse. Surface tension on the seas, based
on wind currents and temperatures among other factors, helps control how fast
oil will spread and greatly controls what type of technologies work best. Choppy
seas or fast currents, for example, can render booms and skimmers relatively
useless but might be perfect for dispersants or sorbents, Callahan says.
Responders also have to look at “the type of environment the oil is headed
for,” Callahan says, to know what type of technologies can or cannot be
used there. For example, he says, sandy beaches are easier to clean up than
marshes or protected embayments, which are highly sensitive environments where
responders cannot “go tramping about with shovels and rakes.” Responders
also consider the impacts of the spill and their potential responses on the
habitats involved, such as fisheries or marine reserves.
Lastly, responders must “assess the balance of tradeoffs” of the particular
technologies chosen, Callahan says, in deciding how to respond. For example,
some of the alternative technologies, especially dispersants, are still somewhat
controversial, says Don Aurand, vice president and senior scientist at Ecosystem
Management & Associates, Inc., an environmental consulting firm in Maryland.
“Dispersants put oil into the water column, thus providing more exposure
to fish,” he says. “A lot of people view that as an issue.” Then
again, he says, dispersants protect shorelines from oil. “The goal is to
minimize overall damage and promote recovery by making intelligent choices.”
During a spill, responders generally will utilize several different technologies.
During the Katrina cleanup, for example, responders used almost all of them.
At Chevron’s Empire terminal, most of the oil was contained onsite where
it naturally dispersed, according to the Coast Guard. Responders contained the
rest of the oil using mechanical booms, and cleaned it up with a skimmer and
in situ burning. Much of the oil at Empire spilled out in marshes, which previously
had been overrun by an invasive plant species, Callahan says, so in situ burning
killed two birds with one stone — wiping out the oil as well as the invasive
species. Some other cleanup sites also used sorbents, but no sites employed
dispersants, as that particular technology is only used in the deep sea.
All of the players in the command group stay involved in the process from initial
cleanup through restoration of affected sites, Callahan says. Months after Katrina,
NOAA is still involved in cleanup and restoration projects at several of the
spills.
The big picture
There are two realities of oil spills, Aurand says: They are inevitable but
unpredictable, and “you’re not going to be able to clean it all up
with mechanical recovery techniques.” So the emphasis, he says, has to
be on using whatever combination of technologies necessary to leave the smallest
footprint, and on ensuring that good contingency plans are in place for any
possible spills.
NOAA responds to about 100 incidents every year on average, varying in size
and impact, Callahan says. The Coast Guard responds to many more spills, he
says, “but this would include smaller events where it is more of a law
enforcement action” that does not call for NOAA scientific support.
This past year was certainly anomalous in terms of the number of spills, especially
since 1990, when Congress passed the Oil Petroleum Act of 1990 into law (following
the Exxon Valdez spill), says Robin Rorick, a senior regulatory analyst with
the American Petroleum Institute, an industry trade group in Washington, D.C.
Among other provisions, the act established double-hull provisions for tankers,
strengthened spill response penalties and established the Oil Spill Liability
Trust Fund.
The fund, originally established by a per-barrel tax on the petroleum industry,
is intended to be an immediately available source of funding should a spill
occur or should a company not have enough money to cover the cleanup costs,
Rorick says. The fund is also used to finance oil spill prevention and response
activities of various federal agencies as well as research into new and improved
oil spill response technologies. “Overall, industry’s record on oil
spills is excellent, especially considering the amount of petroleum products
[that are] produced and transported in our country, but it is not perfect,”
Rorick says. “That said, industry is continually striving to improve its
oil spill record — if not make it perfect.”
“We’re always looking at ways to optimize spill response strategies,”
says Clark of ExxonMobil, from identifying oil slicks in the water to sending
the appropriate cleanup equipment. Although the actual cleanup technologies
have been in use for the last several decades or so, the technologies “have
steadily advanced and are continuing to advance today,” says Joseph Mullin,
manager of the Minerals Management Service (MMS) Oil Spill
Response Research Program, which is financed by the trust fund.
Booms and skimmers that used to move at 0.5-knot speeds, for example, now reach
3 knots, covering four times as much ground in the same time, Mullin says. And
recently, research and development programs at NOAA, MMS and ExxonMobil, among
others, have largely focused on developing computer models for oil spill tracking
and improving remote sensing and surveillance, as well as conducting dispersant
effectiveness experiments at Ohmsett, the National Oil
Spill Response Test Facility located in Leonardo, N.J.
“We’re using advanced computer models now to develop scenarios for
the trajectories of oil spills, and also to look at the chemistry of what happens
as the oil moves,” to help evaluate treatments, Clark says. Temperatures,
winds and other seasonal weather conditions all affect the trajectories of where
an oil spill will drift, so better modeling will help determine how to intercept
the spill. Additionally, chemical and physical properties of oil change as it
moves through water, with or without the aid of dispersants, he says, so it
is important to track exactly what is happening to know what the best cleanup
technology is.
Remote sensing is also aiding in the tracking of oil. Researchers use radar
to track oil spills at night or in cloudy conditions, to direct cleanup equipment
to the thickest areas first, and to determine the type of oil spilled, Clark
says.
Researchers are also working on new ways to find oil under ice, Mullin says.
Currently, pipelines underneath ice in Alaska and the North Sea pump oil onshore,
requiring the drilling through ice to find a spill, he says. “That’s
not a good option.” So, ExxonMobil is working on using ground penetrating
radar to look through the ice for spills, which requires no drilling. They have
a permit to test the technology in Norway in April.
Practicing oil spill scenarios — contingency planning — is also a
big part of the oil spill response, and a part that takes place long before
a spill occurs, Clark says. “All the oil companies make a concerted effort”
to ensure their contingency plans are updated and using the best technologies.
Avoiding spills is impossible, Callahan adds, so being prepared is “the
best medicine.”
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