(04\/22\/2011)<\/p>\n
Paul Quinlan, E&E reporter<\/p>\n
One word could describe U.S. EPA’s oversight of BP PLC’s decision to
\npour 1.84 million gallons of oil-dispersing chemicals into the Gulf of
\nMexico during the Deepwater Horizon oil spill: uncertain.<\/p>\n
Responding to growing public unease last year over BP’s strategy of
\nfighting a massive chemical spill with more chemicals, EPA flexed its
\nregulatory muscle. The result was not confidence-inspiring: a shoving
\nmatch between the world’s largest environmental regulator and one of
\nthe world’s largest oil companies that showed how little the regulators
\nunderstood about oil dispersants.<\/p>\n
One year later, scientists say little has changed.<\/p>\n
Decision making about the use of dispersants to combat the oil pouring
\nout of the Macondo well 5,000 feet below the Gulf surface were driven
\nmore by politics, circumstances of supply and availability, and
\neducated guesswork than by informed science, experts say.<\/p>\n
Some questions posed during the spill have been answered. For example,
\nthe chemical constituents of the dispersant used has been published by
\nEPA and shown in rudimentary tests to be no more toxic or less
\neffective than competing alternatives.<\/p>\n
But since the Obama administration has resumed issuing drilling permits
\nin the Gulf of Mexico, the most important questions remain unanswered:
\nHow much did dispersants — as opposed to simple physics –contribute
\nto keeping oil underwater and out of Louisiana’s marshes? How effective
\nwas underwater injection of the dispersants onto the wellhead? And what
\nlong-term effects will the lingering chemicals and the dispersed oil
\nhave on the Gulf of Mexico ecosystem?<\/p>\n
“There are so many data gaps and uncertainties with the use of
\ndispersants and their effects,” said Carys Mitchelmore, an
\nenvironmental chemist and toxicologist at the University of Maryland’s
\nCenter for Environmental Science and co-author of a 2005 National
\nResearch Council report on oil dispersants. “Why hasn’t there been the
\nfunding available to look into some of these things?”<\/p>\n
After last year’s spill began, regulators seemed confused. Twenty days
\nafter the rig explosion, on May 10, EPA told BP to monitor and assess
\nits use of oil dispersants. Ten days later, the agency ordered the oil
\ngiant to switch from Corexit-brand dispersant to one of several others
\nbelieved to be “less toxic and more effective.” BP declined and
\ndefended its choice. EPA criticized the company’s response as
\n“insufficient” and ordered BP to “significantly scale back” dispersant
\nuse. BP did not (Greenwire, June 24).<\/p>\n
EPA Administrator Lisa Jackson now defends her agency’s call to allow
\nBP to fight the spill using dispersants. “The chemicals helped break up
\nthe oil,” Jackson told The New York Times in a recent interview.”It
\nwas the right decision to use them.”<\/p>\n
If that is the case, then on what basis did EPA decide to order BP to
\nramp down dispersant use on May 26, two months before the well was
\ncapped? EPA officials declined to comment. But other experts have
\nspeculated.<\/p>\n
“My view is that I think EPA was responding a bit to public concern and
\npressure,” said Ron Tjeerdema, an environmental toxicologist and oil
\ndispersants expert at the University of California, Davis.Tjeerdema
\nwas one of 50 scientists, engineers and spill responders that the
\nNational Oceanic and Atmospheric Administration assembled during the
\nspill to decide whether to continue using dispersants. The panel
\nconcluded that dispersant use should continue.<\/p>\n
At that point, questions lingered over whether a better alternativet o
\nCorexit existed. A table listing 19 dispersants alongside crude
\nmeasures of the toxicity and effectiveness of each — part of the
\nNational Contingency Plan (NCP) Product Schedule on file at EPA —
\nindicated that two Corexit formulas, 9500A and 9527A, might be among
\nthe most toxic and least effective formulas in breaking up South
\nLouisiana crude oil (Greenwire, May 13).<\/p>\n
The table became the basis of EPA’s decision, under pressure from
\nCongress and the public, to order BP to switch to one of the listed
\nalternatives. Mitchelmore said she later found problems and
\ninconsistencies in the testing methods that produced the data listed in
\nthe NCP product schedule table’s toxicity and effectiveness ratings.<\/p>\n
By then, EPA had already ordered BP to switch to something other than
\nCorexit. Upon BP’s refusal, EPA launched its own tests to see if a
\nbetter alternative existed. The results came back two months later on
\nAug. 2, around the time the well was capped. To the agency’s chagrin,
\nBP was shown to be right. EPA’s tests showed Corexit 9500A was no more
\ntoxic or less effective than any of the competing products, all of
\nwhich were stockpiled in vastly smaller and ultimately insufficient
\nquantities (E&ENews PM, June 30).<\/p>\n
From the early days of the spill, BP’s purchase of Corexit represented
\na third of the world’s supply. After the spill, in November, the
\nfederal government’s Oil Budget Calculator report said of dispersant
\nuse: “… were it a spill by itself, it would be one of the larger
\nspills in U.S. waters.”<\/p>\n
But the scarcity of Corexit alternatives made the decision about
\nwhether to switch to some other brand “a moot choice,” according to
\nTjeerdema.<\/p>\n
“The oil industry generally only stockpiles one at a time,” he said.
\nTjeerdema recalled chuckling to himself over news reports that BP began
\ndispersing oil using Corexit 9527, an older formula that dates back to
\nthe 1980s, before switching to 9527A.<\/p>\n
“Right away, I understood they were getting rid of their old stockpile
\nthat they hadn’t used for 20 years,” Tjeerdema said.”They’re kind of
\nefficient in wanting to get the most out of their stockpiled
\ndispersants.”<\/p>\n
Breaking up is hard to do<\/p>\n
Dispersants are frequently compared to dish soap — and in fact, share
\nsome of the same ingredients. The chemicals break up oil — which
\notherwise tends to cluster and float — into tiny droplets that can
\nsink and diffuse into the water column, so that bacteria and marine
\norganisms can more easily consume them.<\/p>\n
Given the shortage of equipment available during the Deepwater Horizon
\nspill to burn, skim or otherwise dispose of the oil at the surface, the
\nquestion becomes one of environmental tradeoffs: Should the oil be
\nsunken with dispersants, at possible risk to deepwater marine
\necosystems, or be allowed to surface on its own and float onto beaches
\nand into marshes?<\/p>\n
Tjeerdema, who served on the NOAA panel that recommended continued
\ndispersant use for the spill last June, stands by the group’s consensus
\nthat dispersing the oil was “less environmentally harmful” than
\nallowing crude to migrate into the coastal marshes and wetlands along
\nthe Louisiana coast, which act as nurseries for economically important
\nfish and shellfish and can be almost impossible to clean.<\/p>\n
“If you take dish detergent and squirt it to your aquarium, it will
\ncertainly kill your fish,” Tjeerdema said. “If you can put 2 million
\ngallons of dispersant into the environment in a way that it will mix
\nand bind with the oil to reduce overall toxicity, maybe that’s nots uch
\na bad thing.”<\/p>\n
But the chemicals do not just disappear. In the most comprehensive
\nstudy on the fate of oil dispersants used in the Gulf spill, Liz
\nKujawinski, an associate scientist of marine chemistry at the Woods
\nHole Oceanographic Institution, found that a key ingredient in the
\ndispersants — dioctyl sodium sulfosuccinate, or DOSS — remained
\ntrapped in the underwater plume of oil that had spread 180 miles from
\nthe well by September, even as it became almost undetectably dilute.<\/p>\n
“There was sort of a public perception that the dispersant was just
\ngoing to go away,” Kujawinski said. “We concluded that dilution was
\nreally the primary process.”<\/p>\n
But Kujawinski reserves judgment on whether or not dispersing the oil
\nwas a good idea. For one, she says, not enough data exists to show what
\neffect, if any, dispersants sprayed deep underwater had on breaking up
\nthe oil gushing from the wellhead. She and other researchers note that
\nsimple physics may have done more to keep the oil trapped in underwater
\nplumes.<\/p>\n
Rather than second-guess the response, Kujuawinski says research should
\nbe devoted to answering the most important questions: Did dispersants
\nplay a significant role in breaking up the oil at the wellhead and
\nshould sinking the oil have been the goal at all?<\/p>\n
“We need to take a step back and say it’s happened and then say whether
\nor not it did what it’s supposed to do,” she said, noting that
\nresponders had limited equipment for skimming and burning oil that rose
\nto the surface.<\/p>\n
“The known negative impact of swamping the marsh with oil –that’s a
\nknown problem,” Kujawinski said. “The big question is whether or not
\nthey caused a different problem.”<\/p>\n
Answers may not be forthcoming soon. As dolphins and sea turtles
\ncontinue to wash up mysteriously on the Gulf Coast, only $40 million of
\nthe $500 million BP has committed to Gulf research has been disbursed
\nso far because of organizational delays. EPA has proposed additional
\nresearch into oil dispersants toxicity and effectiveness in 2012,
\nalthough the agency has come on the chopping block and already faces
\n$1.6 billion in cuts under the budget deal approved last week –likely
\nthe first of many such spending fights.<\/p>\n
For now, the puzzle surrounding dispersants remains unsolved, said Lisa
\nSuatoni, senior scientist with the Natural Resources Defense Council.<\/p>\n
“In the end, we would hope that the government and BP would have a will
\nto put together that puzzle, and it’s not all clear from the research
\nthat’s coming out that they do have that will,” she said. “It’s a
\nlittle discouraging if the interest in oil spill response research
\nlasts only as long as the oil spill response.”<\/p>\n
Special thanks to Richard Charter<\/p>\n","protected":false},"excerpt":{"rendered":"
(04\/22\/2011) Paul Quinlan, E&E reporter One word could describe U.S. EPA’s oversight of BP PLC’s decision to pour 1.84 million gallons of oil-dispersing chemicals into the Gulf of Mexico during the Deepwater Horizon oil spill: uncertain. Responding to growing public unease last year over BP’s strategy of fighting a massive chemical spill with more chemicals, … Continue reading E&E:More questions than answers on dispersants a year after spill<\/span>