Monday, May 31, 2010

Disaster by design, the Deepwater Horizon blowout

The April 20, 2010, blowout of an oil and gas well in the Gulf of Mexico, south of the Louisiana coast, created the worst environmental crisis for the United States since the massive dust storms of Great Depression years. Both occurred because of mismanaged natural resources, but otherwise they greatly differed. The Dust Bowl was a result of hundreds of thousands of farmers tilling marginal land without crop rotation, leaving soils vulnerable to severe drought. [1] The well blowout came from a highly concentrated activity, involving a few hundred people attempting to access a high-pressure reservoir, drilling from the high-technology Deepwater Horizon platform in about one mile water depth without adequate margins of safety. [2]

Both disasters might have been prevented by adequate government regulation. In the 1920s, when it would have mattered most, there was hardly any government presence in agriculture other than the field stations set up by states and the federal government to assist with, but not to regulate, crop management. The federal government and many states were in the grip of deeply conservative, even reactionary administrations, firmly opposed to government regulations. Their closest approach had been the federal Pure Food and Drug Act of 1906, passed during the Theodore Roosevelt administration and largely aimed at unsanitary meat packing. [3]

The 2010 Gulf of Mexico well blowout came 41 years after a similar disaster, the 1969 well blowout in Santa Barbara Channel, a few miles off the California coast. Shocked by gross pollution of the Pacific coastline, Congress swiftly passed the National Environmental Policy Act of 1969. [4] It formed a basis of regulation that had become institutionalized in missions of government agencies by the time of the 2010 disaster. Yet like the Pure Food and Drug Act, the National Environmental Policy Act proved susceptible to manipulation and evasion. Regulations created and enforced under it failed to prevent a catastrophe, even though when one occurred the federal government was a progressive administration committed to environmental protection.

The major cause of the 2010 Gulf of Mexico well blowout was quickly assessed, only several days after public release of a well schematic. [5] Dr. Arthur Berman, a Houston petroleum geologist, showed that unsafe design for the Macondo 1 well had left unrestrained areas of bare drillhole, above a high-pressure oil and gas reservoir, connected to the sea floor through an annulus between metal casings. [6] His analysis of the final cementing operation was soon confirmed through a public release of data from the well owner. [7] What had yet to be released at that point were documents showing the faulty design as submitted to and approved by the Minerals Management Service (MMS), an agency of the U.S. Department of the Interior set up to supervise offshore oil and gas operations.

As of 2010, MMS had managed federal leases of outer continental shelf lands and supervised their operations for 28 years, under authority of the Federal Oil & Gas Royalty Management Act of 1982. Many responsibilities were created by the National Environmental Policy Act, which requires environmental impact statements for such activities. During several years before the 2010 blowout, MMS had been repeatedly troubled by mismanagement and corruption. In 1998 and subsequent years major blunders occurred. Faulty contracts allowed leaseholders to avoid many billions of dollars in oil and gas royalties, disclosed by the New York Times February 15, 2006. Although the problems were discovered within MMS in 2004, MMS took no action to correct them until the public disclosure, according to the inspector general for the Interior Department. [8]

MMS had long paid cash bonuses to employees for expediting work related to oil and gas development, a key element in creating a corrupt job environment. [9] In 2008 MMS was found by its inspector general to host what he called a "culture of ethical failure." Abuses cited included patronage, inside dealing, kickbacks, revolving door employment and misuse of federal property--extending over a period of at least four years. As a result of the investigation several employees were reassigned, some quit, and at least one was convicted of a felony. [10]

In 2010 the Macondo 1 well blowout in the Gulf of Mexico led reporters to discover that its lease and many other projects in the Gulf of Mexico had been exempted by MMS from environmental reviews. As a result, companies had not been required to prepare and document emergency responses. The Deepwater Horizon platform lacked a fail-safe blowout preventer, and the Macondo 1 well owner lacked salvage equipment. In budget documents MMS had claimed efficiency from using "categorical exclusion" for a "streamlined" form of environmental review. [11] What the agency did was generate a prepackaged deal for companies. A pro-forma environmental review was prepared by and approved within the agency. After companies paid for leases, they were automatically exempted from reviews, and their applications to conduct operations were, quite literally, rubber-stamped.

The Macondo 1 well was mainly regulated under a "multisale EIS" (Environmental Impact Statement) covering 11 Gulf of Mexico leases, prepared by MMS staff in 2007. Its risk analysis finds that over 40 years, "there is a 69-86 percent chance of one or more spills [of] 1,000 barrels [or more] occurring" [page 4-231]. The "multisale EIS" finds substantial risk that a spill of 1,000 or more barrels will pollute many miles of coastline [page 4-234]. It also indicates that pollution can persist for many years [page 4-238]. Thus MMS knew that a disaster in this area was likely and that consequences would probably be widespread and long-lasting. [12]

The exploration plan filed with MMS to drill the Macondo 1 well described a worst-case oil discharge as 300,000 barrels per day, giving a number without saying "barrels." However, MMS instructions for such plans show daily volume in barrels. In less than 12 days such a discharge would exceed the world's worst ocean oil disaster, the 1979 Ixtoc 1 well blowout, also in the Gulf of Mexico. MMS knew the Macondo 1 well had the potential to cause a catastrophe, yet it gave the plan routine approval, letting the owner go ahead without documented procedures for responding to such a radical emergency. [13]

Immediately after the Macondo 1 well blowout the U.S. Coast Guard failed to mount coordinated rescue, control and salvage operations. Years of focusing on terrorism rather than natural and industrial disasters had left it unprepared for such an event. MMS permitted relief wells without requiring any more safety preparation than it had required for the well that blew out. The U.S. National Oceanic and Atmospheric Administration distributed a hasty assessment of the crude oil discharge rate that was soon shown to be scientifically faulty, and then it refused to release data and methods. The U.S. Environmental Protection Agency issued a hasty decision endorsing untested use of large quantities of dispersants, when environmental evidence showed that similar chemicals had led to long term environmental damage. [14]

Despite contributions to the problems, the Coast Guard and MMS were put in charge of an initial investigation. [15] Outrage over crude oil reaching beaches and marshland and protests over a compromised investigation led to a rapid series of actions: reorganization plans for the MMS, resignation of the MMS director, suspension of all offshore drilling in deep water, new drilling permits and offshore oil and gas leasing, and appointment of a Presidential investigating commission. [16] The U.S. Geological Survey prepared an estimate of the discharge, putting it at 12 to 19 thousand barrels (500 to 800 thousand gallons) of crude oil per day. [17]

Through May, 2010, the Macondo 1 well owner tried a series of maneuvers to trap or plug the oil discharge, without much success. Similar maneuvers had been tried with previous subsea well blowouts, notably the 1979 135F platform, Ixtoc 1 well blowout in the Bay of Campeche off Mexico. Despite the same kinds of attempts, that blowout flowed for 290 days, discharging an estimated 120-200 million gallons of crude oil into the southern Gulf of Mexico, the world's greatest accidental ocean oil disaster so far. [18]

Sometimes such maneuvers succeeded, as with the 1977 Bravo platform, well B14 blowout in the North Sea off Norway. But when reservoir pressure was high and consequent gas flow was strong they failed, as they recently did with the Montara platform, well H1 blowout in the Timor Sea off northwest Australia, which flowed for 70 days. [19] Company and U.S. officials lied, saying the Macondo 1 well blowout was "unprecedented," and success of the maneuvers would be unpredictable. All that was really unprecedented was water depth. There was otherwise substantial experience with similar blowouts, but there was an unprepared industry and a similarly unprepared government. [20]

The blowout preventer (BOP) configured for the Deepwater Horizon platform failed; otherwise the blowout would have been prevented. That failure was also by design, as the U.S. Minerals Management Service has been made fully aware. [21] Current-generation blowout preventers depend on shearing blind rams (SBRs) to cut drill pipe, so as to allow floating platforms like Deepwater Horizon to seal a well, disconnect from it and move away. Current-generation SBRs cannot cut through pipe joints, the enlarged, hardened sections of steel that join segments of drill pipe. About ten percent of the lineal extent of drill pipe is joint. However, BOP rams do not close with a snap. Their hydraulic systems are regulated, and they take most of a minute to close. During that time the force of a blowout is pushing drill pipe upward. As an SBR nears the point of full closure, inevitably an upward-moving pipe joint lodges in it. After trapping the pipe joint, the SBR then cannot cut it.

U.S. government says it will revise offshore oil and gas regulations and agency organizations. However, few if any people working in U.S. government actually know what to do. In the aftermath of the 1969 Santa Barbara disaster laws were written, but then they were often ignored. If the aftermath of the 1979 Bay of Campeche catastrophe, industry developed a slightly improved blowout preventer (in use at the Macondo 1 well), and U.S. government prepared a few internal studies. [22] As a result, MMS knew that existing offshore oil and gas well development was unsafe and knew that neither government nor industry was prepared for a major emergency, but it failed to generate plans, conduct relevant research, arrange for improved equipment and supplies, perform engineering evaluations or coordinate such efforts with companies or other agencies. Decades of opportunity were squandered, leading to another catastrophe.

[1] R. Douglas Hurt, The Dust Bowl: An Agricultural and Social History, Burnham, 1981.

[2] Tom Fowler, Experts have their doubts on well's design, Houston Chronicle, May 26, 2010, available at Ian Urbina, Documents show early worries about safety of rig, New York Times, May 30, 2010, available at

[3] James Harvey Young, Pure Food: Securing the Federal Food and Drugs Act of 1906, Princeton University Press, 1989.

[4] Matthew J. Lindstrom and Zachary A. Smith, The National Environmental Policy Act: Judicial Misconstruction, Legislative Indifference and Executive Neglect, Texas A&M University Press, 2002.

[5] U.S. House Energy and Commerce Committee, Testimony of Timothy Probert, May 12, 2010, available at

[6] Arthur E. Berman, What caused the Deepwater Horizon disaster? The Oil Drum, May 21, 2010, available at

[7] U.S. House Energy and Commerce Committee, BP presentation: Deepwater Horizon interim incident investigation, May 24, 2010, available at (19 MB), page 14.

[8] Edmund L. Andrews, U.S. has royalty plan to give windfall to oil companies, New York Times, February 15, 2006, available at Edmund L. Andrews, Oil lease chief knew of error, report asserts, New York Times, January 18, 2007, available at Inspector General, Interior Department, Lack of price thresholds in Gulf of Mexico oil and gas leases, January 2007, available at

[9] Edmund L. Andrews, As profits soar, companies pay U.S. less for gas rights, New York Times, January 24, 2006, available at William Yardley, Arctic drilling proposal advanced amid concern, New York Times, May 20, 2010, available at Juliet Eilperin, U.S. agency overseeing oil drilling ignored warnings of risks, Washington Post, May 25, 2010, available at

[10] Charlie Savage, Sex, drug use and graft cited in Interior Department, New York Times, September 10, 2008, available at Inspector General, Interior Department, OIG investigations of MMS employees, Re: Gregory W. Smith, MMS Oil Marketing Group and Federal Business Solutions contracts, September 9, 2008, available at

[11] Juliet Eilperin, U.S. exempted BP's Gulf of Mexico drilling from environmental impact study, Washington Post, May 5, 2010, available at Minerals Management Service, Budget justification and performance information, fiscal year 2010, available at, page 85.

[12] Minerals Management Service, Gulf of Mexico Oil and Gas Lease Sales, 2007-2012, Nos. 204, 205, 206, 207, 208, 210, 213, 215, 216, 218 and 222, Final Environmental Assessment, Volumes 1 and 2, April 2007, available at and

[13] Minerals Management Service, Initial exploration plan, lease OCS-G32306, block 252 Mississippi Canyon area, March 10, 2009, available at (rubber-stamped NOTED-SCHEXNALIDRE). Minerals Management Service, Contents of plan (Appendix A NTL No. 2006-G14 Guidance for MMS-137 OCS Plan Information Form, August 2003), available at

[14] Scott Berinato, Coast Guard, DHS and Deepwater: same ship, different day, CSO Magazine, May 1, 2004, available at Susan Saulny, Finger-pointing, but few answers at hearings on drilling, New York Times, May 12, 2010, available at Ian Urbina, U.S. said to allow drilling without needed permits, New York Times, May 14, 2010, available at Justin Gillis, Scientists fault U.S. response in assessing Gulf oil spill, New York Times, May 20, 2010, available at Lynn Yaris, Caution required for Gulf oil spill clean-up, Lawrence Berkeley National Laboratory, May 4, 2010, available at Jason Dearen and Ray Henry, Associated Press, Chemicals used to fight Gulf of Mexico oil spill a trade-off, New Orleans Times-Picayune, May 5, 2010, available at

[15] The White House, President Barack Obama, Administration-wide response to BP spill, May 3, 2010, available at "Secretary Napolitano and Secretary Salazar signed an order establishing the next steps for a joint investigation that is currently underway into the causes of the explosion of the drilling rig Deepwater Horizon in the Gulf of Mexico. The U.S. Coast Guard (USCG) and the Minerals Management Service (MMS) share jurisdiction for the investigation." Matthew L. Wald, Independent inquiry into oil spill is urged, New York Times, May 15, 2010, available at

[16] John M. Broder and Shaila Dewan, White House to create panel to study Gulf oil spill, New York Times, May 18, 2010, available at Juliet Eilperin and Scott Wilson, Birnbaum 'took fall' after MMS played catch-up after lapses in ethics, oversight, Washington Post, May 29, 2010 available at Debbi Wilgoren and Michael D. Shear, Obama to ban new deepwater oil wells, cancel lease sales off Virginia and Alaska coasts, Washington Post, May 27, 2010, available at Juliet Eilperin and David A. Fahrenthold, Graham, Reilly to lead investigation of oil spill, Washington Post, May 22, 2010, available at The White House, President Barack Obama, Executive order, National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling. May 22, 2010, available at

[17] Tom Zeller, Jr., Estimates suggest spill is biggest in U.S. history, New York Times, May 28, 2010, available at Flow Rate Technical Group, U.S. Geological Survey, Flow Rate Group provides preliminary best estimate of oil flowing from BP oil well, May 27, 2010, available at

[18] Energy Resources Co., Ixtoc oil spill assessment, final report, U.S. Bureau of Land Management, March, 1982, available at March Schliefstein, BP's "top kill" process fails, forced officials to attempt yet another strategy, New Orleans Times-Picayune, May 30, 2010, available at Jeffrey Kluger, As top kill drags on, BP's credibility problems grow, Time, May 28, 2010, available at,8599,1992627,00.html.

[19] David Prestipino, Cause of western Australia oil spill revealed, Western Australia Today, November 10, 2009, available at Montara Commission of Inquiry, Australia Ministry for Resources and Energy, multiple documents available at

[20] Steven Mufson and Michael D. Shear, Pressure grows for action by BP, Washington Post, May 1, 2010, available at Debbi Wilgoren, Joel Achenbach and Anne E. Kornblut, Gulf Coast oil spill may take months to contain, officials say, Washington Post, May 3, 2010, available at

[21] West Engineering Services, Shear ram capabilities study, Minerals Management Service, September, 2004, available at

[22] PCCI Marine and Environmental Engineering, Oil spill containment, remote sensing and tracking for deepwater blowouts, Minerals Management Service, August, 1999, available at West Engineering Services, Mini shear study, Minerals Management Service, December, 2002, available at West Engineering Services, Evaluation of secondary intervention methods in well control, Minerals Management Service, March, 2003, available at

Saturday, May 22, 2010

Making an energy extraction disaster worse

Extracting energy from natural resources often carries hazards that are not well known. Because of the April, 2010, explosion at the Upper Big Branch mine in West Virginia, some hazards of coal mining are once again widely publicized, [1] although coal mine disasters have been common for near two centuries. [2] But other coal mining hazards, including stream disturbance from subsidence, methane discharges, underground fires and the vast destruction of environment from surface mining, remain little known to most of the public. [3]

When disasters occur while extracting energy from natural resources, human errors can make them worse. April of 2010 has been a cruel month. Several incidents during the Macondo 1 well blowout in the Gulf of Mexico, including origins of the blowout itself, appear to come from human errors that should have been preventable. [4] Few of the many errors are more vexing than acts of U.S. government agencies trying to respond to that disaster.

Evidence from news reports suggests little or no U.S. Coast Guard planning and coordination for responses to the immense fire. Water, sprayed from several vessels on the fire, entered pontoons of the semi-submersible Deepwater Horizon platform, causing it to capsize and sink after about a day and a half. [5] The huge volumes of natural gas and oil discharges continued to burn at the sea surface, but water sprays were then used to extinguish the fire. As previous ocean oil disasters showed, like the 1979 Ixtoc 1 well blowout in the southern Gulf of Mexico, sea surface fires can burn more than half of blowout discharges, reducing environmental impacts. [6] Through mid-May, 2010, the Coast Guard had provided no detailed public explanation of its actions.

The U.S. Environmental Protection Agency issued instructions allowing the U.S. Air Force and BP, owner of the Macondo 1 well, to apply hundreds of thousands of gallons of dispersant chemicals, both on the sea surface and on the sea floor in the vicinity of discharges from the Macondo 1 well. [7] Short-term effects of dispersant chemicals on marine environments are only partly known, and long-term effects are often unknown.

There have been controversies over the use of dispersants in ocean oil disasters ever since their first major application, following the 1967 Torrey Canyon disaster off the southwest coast of England. Studies suggest long-term hazards, leaving treated coastal environments more disturbed than environments where no cleanup was attempted. [8] The EPA has had decades to evaluate dispersants, but its research has been meager, leaving the agency unprepared in emergencies to respond on the basis of thorough scientific knowledge. In an apparent attempt to mitigate hazards of dispersants being used for the Macondo 1 well blowout, EPA issued supplementary instructions to BP on May 20, 2010. [9] A simultaneous press release said that EPA intended to require use of "less toxic" chemicals. [10]

EPA maintains short-term acute toxicity information for dispersants. [11] Two marine species are used to rate "50 percent lethal concentration" (LC50) in parts per million for approved dispersants: the inland silverside (Menidia beryllina), an estuary fish, after 96 hours exposure, and the oppossum shrimp (Mysidopsis bahia), also an estuary dweller, after 48 hours exposure. In addition, there are "effectiveness" ratings for two crude oils, "Prudhoe Bay Crude" and "South Louisiana Crude." EPA has published testing procedures for the ratings. [12]

As of mid-May, 2010, the EPA-maintained National Contingency Plan Product Schedule included fifteen dispersant products, three of them under multiple trade names. [13] They are listed here in the order of least toxic to most toxic, by 96-hour exposure LC50 ratings in parts per million for Menidia beryllina:

DispersantToxicity LC50, ppmToxicity LC50, ppmEffectiveness
  ProductMenidia beryllinaMysidopsis bahiaSo. La. Crude
MARE CLEAN 2001996    96-hr938    48-hr84.1%
JD-2000407.00 96-hr90.50 48-hr77.8%
NEOS AB300091.1   96-hr33.0   48-hr89.8%
NOKOMIS 3-AA34.22 96-hr20.16 48-hr65.7%
ZI-40031.76 96-hr20.96 48-hr89.8%
SEA BRAT #430.00 96-hr14.00 48-hr60.6%
NOKOMIS 3-F429.80 96-hr32.20 48-hr64.9%
SAF-RON GOLD29.43 96-hr63.00 48-hr53.8%
COREXIT EC9500A25.20 96-hr32.23 48-hr54.7%
SPILLCLEAN24.30 96-hr10.00 48-hrN/A
COREXIT EC9527A14.57 96-hr24.14 48-hr63.4%
BIODISPERS13.46 96-hr78.90 48-hr63.0%
FINASOL OSR 5211.66 96-hr9.37 48-hr71.6%
DISPERSIT SPC 10003.5   96-hr16.6 48-hr105   %
JD-1091.90 96-hr1.18 48-hr91   %

In the May 20, 2010, EPA instructions to BP the key sentence reads, "...BP shall identify...dispersant products from the National Contingency Plan Product Schedule that...have a toxicity value less than or equal to 23.00 ppm LC50 toxicity value for Menidia or 18.00 ppm LC50 for Mysidopsis...." News reports indicated BP was following EPA instructions literally, [14] saying BP had been using Corexit EC9500A, rated at 96-hour LC50 of 25.2 parts per million for Menidia beryllina, but after the May 20 EPA instructions was ordering Dispersit SPC 1000, rated at 96-hour LC50 of 3.5 parts per million for Menidia beryllina.

EPA has provided no rationale for the specific criteria in its May 20 instructions. Their obvious effect is to allow use of the dispersant products Finasol OSR 52, Dispersit SPC 100 and JD-109. It is not clear whether Spillclean would qualify; it has LC50 for Mysidopsis less than 18 but LC50 for Menidia greater than 23, and it lacks an "effectiveness" rating. It is also not clear whether Corexit EC9527A or Biodispers would qualify; they have LC50 for Menidia less than 23 but LC50 for Mysidopsis greater than 18. The instructions say "or" as to LC50 ratings but have ambiguous grammar.

Well known to environmental workers, "a lower LC50 means the substance is more toxic," such as effects of metal ions in fish ponds. [15] Whoever wrote and whoever approved the May 20 EPA instructions apparently did not know that lower LC50 means higher toxicity. Whoever generated specific criteria for dispersants seems to have been choosing products to endorse rather than applying environmental knowledge. Superior products in EPA listings, on the basis of their LC50 toxicity ratings, include Mare Clean 200 and JD-2000. However, those products would not satisfy the misguided EPA criteria.

Adverse consequences in this situation were avoided. BP cancelled its order for Dispersit SPC 100 and responded to EPA that it could not find a qualifying dispersant "in sufficiently large quantities to be useful at the time of the spill." EPA rescinded the erroneous instructions, saying it would issue new ones. [16] It is likely that someone at BP saw through the mistake and realized its potential to make an energy extraction disaster worse. Major news media never told and therefore most of the public never learned about gross incompetence shown by the government during this incident.

[1] Jerry Markon, David A. Fahrenthold and Kimberly Kindy, Mine company faulted on safety issues, Washington Post, April 8, 2010, available at

[2] H. B. Humphrey, Historical summary of coal mine explosions in the United States, Bulletin 586, U.S. Bureau of Mines, U.S. Government Printing Office (1960). United States Mine Rescue Association, Historical data on mine disasters in the United States, available at U.S. Mine Safety and Health Administration, Coal fatalities, 1900-2009, available at

[3] Pennsylvania Department of Environmental Protection, The Effects of Subsidence Resulting from Underground Bituminous Coal Mining on Surface Structures and Features and Water Resources (2005), 25 files, available at Robert R. Seal II, Environmental processes that affect mineral deposits in the eastern United States, U.S. Geological Survey, U.S. Department of the Interior (1999), available at Evironment: The price of strip mining, Time 97(12), March 22, 1971, available at,9171,904921,00.html. Davie Rennie, How China's scramble for 'black gold' is causing a green disaster, London Telegraph, February 1, 2002, available at

[4] Janet McConnaughey and Holbrook Mohr, Associated Press, Oil rig reported explosion 3 hours before fire, WFMJ, Youngstown, OH, April 22, 2010, available at "James," Deepwater Horizon: A firsthand account, Mark Levin Show, WABC, New York City, April 30, 2010, transcription available at

[5] Campbell Robertson, Search continues after oil rig blast, New York Times, April 22, 2010, available at Russell Gold, Safety device questioned in 2004, Wall Street Journal, May 3, 2010, available at Les Blumenthal, McClatchy, Blowout preventers often fail, report says, Tacoma, WA, News Tribune, May 1, 2010, available at Michael Kunzelman and Richard T. Pienciak, Associated Press, Feds let BP avoid filing blowout plan for Gulf rig, WTOP, May 6, 2010, available at Susan Saulny, Finger-pointing, but few answers at hearings on drilling, New York Times, May 12, 2010, available at Scott Pelley, interviewer, Blowout: The Deepwater Horizon disaster, 60 Minutes, CBS News, May 16, 2010, available at

[6] Energy Resources Co., Ixtoc oil spill assessment, final report, Bureau of Land Management, U.S. Department of the Interior (1982), available at

[7] Jason Dearen and Ray Henry, Associated Press, Chemicals used to fight Gulf of Mexico oil spill a trade-off, New Orleans Times-Picayune, May 5, 2010, available at Ted Jackovics, Air Force C-130s spray chemical to help break up oil spill, Tampa Tribune, May 10, 2010, available at U.S. Environmental Protection Agency, Dispersant monitoring and assessment directive for subsurface dispersant application, May 10, 2010, available at

[8] Committee on Effectiveness of Oil Spill Dispersants, Marine Board, National Research Council, Using Oil Spill Dispersants on the Sea, National Academies Press (1989), Appendix B, Torrey Canyon, pp. 317-318, available at Robert J. Fiocco and Alun Lewis, Oil spill dispersants, in Pure and Applied Chemistry 71(1), 1999, special issue on oil spill countermeasures, pp. 27-42, available at

[9] U.S. Environmental Protection Agency, Dispersant monitoring and assessment directive, Addendum 2, May 20, 2010, available at

[10] U.S. Environmental Protection Agency, EPA: BP must use less toxic dispersant, May 20, 2010, available at!OpenDocument.

[11] U.S. Environmental Protection Agency, FSOC dispersant pre-approval guidelines and checklist (1995), Table 1, LC50 toxicities and toxicity indices of crude oils for marine organisms, p. A-10.

[12] U.S. Environmental Protection Agency, Methods for measuring the acute toxicity of effluents and receiving waters to freshwater and marine organisms, at U.S Environmental Protection Agency, Swirling flask dispersant effectiveness test, 40 CFR 300, Appendix C (1997), pp. 224-246, available at

[13] U.S. Environmental Protection Agency, National Contingency Plan Product Schedule, for Category select Dispersant, at

[14] Campbell Robertson and Elisabeth Rosenthal, Agency orders use of a less toxic chemical in Gulf, New York Times, May 21, 2010, available at

[15] Tim Gilbert, Copper in fish ponds, Koi Fish Ponds, Denver, Colorado, at

[16] Paul Purpura, BP can continue using controversial dispersant, New Orleans Times-Picayune, May 24, 2010, available at