The Macondo Blowout Environmental Report-DHSG …ccrm.berkeley.edu/pdfs_papers/DHSGWorkingPapersFeb16...Environmental Science, Policy, and Management, University of California, Berkeley

Deepwater Horizon Study Group 3 Environmental Report – January 2011

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The Macondo Blowout Environmental Report

Thomas Azwell, M.S., Doctoral Candidate, Researcher, Department of Environmental Science, Policy, and Management, University of California, Berkeley.

Michael J. Blum, Ph.D., Arnold Early Career Professor in Earth and Ecological Science, Department of Ecology and Evolutionary Biology, Tulane University, New Orleans, Louisiana.

Anthony Hare, Psy.D., Executive Director, Center for Catastrophic Risk Management, University of California Berkeley

Samantha Joye, Ph.D., Professor, Department of Marine Sciences, University of Georgia

Sindhu Kubendran, B.S., Research Associate, University of California, Berkeley

Artin Laleian, Student, Research Associate, University of California, Berkeley

George Lane, Ph.D., Research & Development, Emergency Response Technology. Baton Rouge, Louisiana

Douglas J. Meffert, D. Env., Eugenie Schwartz Professor of River & Coastal Studies, Center for Bioenvironmental Research, Tulane University, New Orleans, Louisiana.

Edward B. Overton, Ph.D., Professor Emeritus, Environmental Sciences, Louisiana State University

John Thomas III., Law Student, Golden Gate University School of Law, San Francisco, California

LuAnn E. White, Ph.D., DABT, Tulane University School of Public Health and Tropical Medicine, New Orleans.

Deepwater Horizon Study Group The Macondo Blowout Environmental Report

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1 Looking Back The Deepwater Horizon oil rig exploded 5,000 feet below the surface of the Gulf of Mexico on

April 20, 2010. The Flow Rate Technical Group estimates the leak initially produced 62,000 barrels of oil a day and eased to 53,000 barrels a day as the reservoir gradually depleted itself. 4.9 million barrels (205.8 million gallons) of oil had discharged into the Gulf of Mexico by the time the well was capped and sealed July 15, 2010. More than 40,000 responders aided control efforts over the course of the 89-day leak and deployed cleanup response technologies, which included containment and absorbent booms to slow the spread of the oil, in-situ burning to combust the oil on the water surface, chemical dispersant applied at the surface and subsea to dilute the oil into the water column, and oil skimmers to contain and remove the oil from the environment.

The purpose of this report is to give a comprehensive environmental impact assessment of the

Deepwater Horizon oil spill, as well as summarize the lessons learned from the spill and its cleanup efforts. The information in this report should provide a more robust guide to future spill response, as well as a better understanding of the risks involved in oil exploration and production. The following section of the report details the changing nature of oil in the environment specific to the Deepwater Horizon spill; outlines the tradeoffs of response tools and decisions made by Incident Command; and serves as the start of a larger conversation regarding regulation, fine assessment, and the need for more investment in developing environmentally-sensitive cleanup technologies.

1.1 Emulsification of Crude Oil When oil enters the environment from spills, ruptures,

or blowouts it undergoes a continuous series of compositional changes that are the result of a process known as weathering. During this physical-chemical process, lighter oil components photo-oxidize to the atmosphere, while heavier oil components typically mix with water to form a viscous emulsion that is resistant to rapid weathering changes. Thus, it is slower to degrade, more persistent in the environment than non-emulsified oil, and more likely to enter the water column. The oil

emulsion’s viscous character poses a threat to marine vegetation through covering and smothering surfaces with which it comes in contact. If the oil emulsion enters the water column and reaches the benthic zone, it may cause permanent damage to root systems, inhibiting the plants’ ability to regenerate. Emulsified oil cannot effectively be recovered by skimming technologies or absorbent booms, chemically dispersed, or burned. Thus, recovery efforts should be prioritized prior to significant emulsion of oil.

In addition to emulsification, oil in the Gulf also was dispersed through natural physical

processes, as well as through interactions with chemical compounds. The net effect of both natural and chemical dispersion was that much of the oil was transformed into tiny droplets with diameters less than 100 microns. Such droplets face significant flow resistance from the water column in their effort to rise to the surface. They are trapped in the deep Gulf environment until degraded by bacteria and are more likely to interact with marine life. This dispersed oil is diluted as it moves away from the wellhead. Some components dissolve into the water column and are available for fairly rapid biodegradation, while more refractory components are only slowly degraded by


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microorganisms. Because the concentration of the dispersed oil is far lower than the concentration of dissolved oxygen in deep Gulf waters, oxygen depletion to levels that could harm marine fauna have not been observed.

1.2 Chemical Dispersants Chemical dispersants are petroleum solvents that move

oil from the water surface to the water column by breaking the oil slick into small droplets. Their use does not reduce the total volume of oil in the environment, but rather changes its distribution and physical properties. The use of chemical dispersants has been described as a “risk-based paradigm” in which tradeoffs between environmental benefits and harms must be weighed prior to their application. The benefits of chemical dispersant use include potential stimulation of microbial degradation of oil and

protection of shorelines. The former alters and/or removes oil from the environment while the latter prevents it from reaching sensitive ecosystems. The potential harms of their use include greater exposure of oil to subsurface marine life; the presence of larger dispersed oil plumes of uncertain fate and environmental impacts when dispersants are applied at depth; no possibility of oil recovery once oil has been dispersed; and a large potential for facilitating oil transport from the ocean surface to the ocean floor by the aggregation and sinking of small oil particles.1

Effective oil cleanup implements technologies that remove oil, and therefore reduce the spill’s

environmental impact. Whether or not chemical dispersants satisfy these criteria has not been established. Tradeoffs between the environmental benefits and the environmental costs of using chemical dispersants exist, and therefore local assessments of the balance between the two should be considered before taking action. For example, in spills where surface oil proximity presents an imminent threat to a shoreline ecosystem, the threat may be greater than the adverse impact of the use of the dispersant. The Joint Industry Oil Spill Preparedness and Response Task Force2 supports the use of chemical dispersants as a first response and assumes net environmental benefit from the outset. However, oil recovery should be preferred to chemical dispersion as a first response, because recovery removes oil from the environment and does not carry the increased ecological exposure to the toxicity of crude oil.3

1.3 In-Situ Burning of Surface Oil The combustion of crude oil forms a mixture of compounds in solid, liquid, and gaseous phases.

The minor components released, including particulate matter (PM), carbon monoxide (CO), sulfur dioxide (SO2), and nitrogen oxides (NOx) can have the greatest direct impact on human health. Volatile organic compounds (VOCs), which evaporate without ignition soon after reaching the

1 Joye, S. B., M. Crespo-Medina, A. Vossmeyer, M. W. Bowles, K. S. Hunter, P. Medeiros, K. Bowles, C. Comerford, A.

P. Teske, C. Arnosti, K. Zeirvogel, T. Yang, A. Diercks, V. Asper, J. P. Montoya, A. Subramaniam, U. Passow, W. S. Moore, C. Benitez-Nelson, and T. Wade (2011). Soot and Slime: Burning and microbial metabolism altered and transported Macondo oil from the sea surface to the seafloor. (in preparation for submission)

2 Joint Industry Oil Spill Preparedness and Response Task Force. "Draft Industry Recommendations to Improve Oil Spill Preparedness and Response." 2010.

3 Bhattacharyya, S., P.L. Klerks, and J.A. Nyman. "Toxicity to Freshwater Organisms from Oils and Oil Spill Chemical Treatments in Laboratory Microcosms." Environmental Pollution 122 (2003): 205-15.


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surface, also are harmful if inhaled. The U.S. Environmental Protection Agency (EPA) considers benzene, toluene, ethylbenzene, and xylene as the “key toxic VOCs”.4

Dispersal of an airborne toxicant plume is controlled by local

environmental factors, primarily wind speed and direction. In previous oil spills where air quality was monitored following burning, concentrations of toxic gases fell to background levels outside approximately two miles from the burn.5 If such dispersal is a general trend and burning takes place more than two miles offshore, harm to the general public – with respect to the aforementioned gases – will not be greatly increased by in-situ burning. Response workers near the burn, however, will be exposed to greater risk, necessitating the use of onboard air monitoring technologies. The burning of oil on the water surface also represents lost opportunities in terms of oil recovery and the subsequent energy production by incineration. Furthermore, the burning of oil on the water surface produces a significant amount of soot, which can be deposited on the seafloor with unknown consequences.5

1.4 Occupational Risk Studies of tanker oil spill responses have reported adverse health effects in response

workers.6, 7, 8, 9 These studies may underestimate the health effects on the Deepwater Horizon response personnel because the spill’s magnitude and duration are unprecedented. Fresh oil generally is more toxic than weathered crude oil because the concentration of volatile organic compounds (VOCs) decreases with weathering. Still, weathered oil contains harmful compounds that can cause irritant reactions, and there is a potential risk for oil to be aerosolized into respirable airborne droplets or volatilized by activities such as pressure washing. Even though detection of hydrocarbon odors is common in areas contaminated by oil, odor is not a reliable indication of a health hazard. Some individuals, though, are bothered by odors and can develop symptoms requiring medical evaluation. Overall, there is an incomplete understanding of the cumulative human health toxicity associated with the particular characteristics of this spill, including a large volume of continuously-flowing oil, extensive dispersant use, and in-situ burning.

According to the Louisiana Department of Health and Hospitals, from April 25 to September

18, 2010, there were 411 reports of health complaints believed to be related to exposure to

4 U.S. Environmental Protection Agency and Centers for Disease Control and Prevention. "Odors from the BP Spill."

Washington D.C., 2010. 5 Barnea, Nir. "Health and Safety Aspects of in-Situ Burning of Oil." edited by National Oceanic and Atmospheric

Administration. Seattle, WA, USA, 2005. 6 Zock JP, Rodriguez-Trigo G, Pozo-Rodriguez F, Barbera JA, Bouso L, Torralba Y, Anto JM, G FP, Fuster C, and

Verea H. Prolonged Respiratory Symptoms in Clean-Up Workers of the Prestige Oil Spill Am J Respir Crit Care Med, 176:610-616, 2007.

7 Aguilera F, Mendez J, Pasaro E, and Laffon B. Review on the Effects of Exposure to Spilled Oils on Human Health. J. Appl. Toxicol. 30:291-301, 2010.

8 Perez-Cadahia B, Mendez J, Pasaro E, Lafuente A., Cabaleiro T, Laffon B. Biomonitoring of human exposure to Prestige Oil: Effects on DNA and endocrine parameters. Environmental Health Insights 2:83-92, 2008.

9 Rodríguez-Trigo G, Zock JP, Isidro Montes I. Health effects of exposure to oil spills. Arch Bronconeumol. Nov;43(11):628-35, 2007.


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pollutants from the oil spill.10 325 of these reports came from response personnel and 86 from the general population. The most frequently reported symptoms were headache, dizziness, nausea, vomiting, weakness/fatigue and upper respiratory irritation. Due to a lack of chemical-specific air monitoring, especially for cleanup workers in vessels, direct correlations between chemical exposure and health complaints cannot be determined. For example, the USEPA’s air monitoring at several fixed sites used a technology known as photoionization detection (PID) that can only measure total VOCs, not specific compounds such as benzene, toluene, ethylbenzene, and xylene. In fact, there are no USEPA records of samples obtained from vessels in which cleanup workers were present.

1.5 Waste Management Louisiana has state regulations in place promoting waste diversion. The state experienced a

previous influx of more than 22 million tons of disaster debris waste in the aftermath of Hurricane Katrina, the largest natural disaster in US history, and recognized the need to reduce materials entering landfills. In addition, Senate Bill (SB) 583 entails the creation of a comprehensive debris management plan with the goal to “reuse and recycle material, including the removal of aluminum from debris, in an environmentally beneficial manner and to divert debris from disposal in landfills to the maximum extent practical and efficient which is protective of human health and the environment (SB 583).” 11 SB 583 prioritizes waste management practices for debris in this order: “recycling and composting; weight reduction, volume reduction; incineration or co-generation and land disposal” to the extent they are “appropriate, practical, efficient, timely, and have available funding (SB 583).”

The spill and its subsequent clean-up methods generated 80,276 tons of solid waste and 956,350

BBLs of liquid waste as of October 17, 2010.12 Detailed waste management plans were created to outline disposal methods to ensure that the disaster waste was properly handled. The US EPA, the US Coast Guard, the Unified Area Command, and the Gulf States directly affected by the spill approved the waste management and disposal plans.

The waste can be separated into categories depending

on the make-up of the material. These categories include solid waste, recovered oil, oily water and liquid waste, and animal carcasses. Solid waste includes oil-contaminated material such as sorbents, debris and personal protective equipment, as well as non-contaminated solids, such as those materials required by the support operations. In the period ending October 26, 2010, 71,844 tons of oily solids and 9,512 tons of solid waste were collected and taken to municipal solid waste landfills.13

10 Louisiana Department of Health and Hospitals, Oil Spill Health Effect Summary, September 18, 2010,

www.dhh.louisiana.gov/offices/publications/pubs-78/_OilSpillSurveillance2010_16.pdf 11 “Recovered Oil/Waste Management Plan Houma Incident Command” 12 “Weekly Waste Tracking Cumulative Report,” BP International, Ltd., October 17, 2010,

http://www.bp.com/genericarticle.do?categoryId=9034343&contentId=7063466 13 Waste, Oil Recovery, and Disposal Summaries,” BP International, Ltd., October 26, 2010,

http://www.bp.com/genericarticle.do?categoryId=9034343&contentId=7063466


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A significant amount of waste generated from the Deepwater Horizon event was from sorbents and booms. However, alternative cleanup technologies to the ones used in this operation are available and are more facilitative to recycling and composting, and therefore are better aligned with the desires laid out by SB 583. For example, natural fiber booms and loose absorbents can absorb the oil and then be composted, resulting in degradation of the hydrocarbons and an end product that can be used or sold as a soil amendment. The State of Louisiana is the largest sugar cane producer in the United States, generating more than 3 million tons of natural fiber waste per year, known as bagasse.14 Preliminary research at UC Berkeley has demonstrated bagasse’s high absorption rate and ability to degrade oil naturally – a process encouraged by the 2% sugar content that remains in the fiber and supports microbial growth after the sugar refining process. Therefore, the use of bagasse to fill booms and as a loose absorbent not only would help to solve a waste problem for the sugarcane industry, it would reinvest revenue spent on cleanup back into the local economy.

Another solution, loose sorbents, can be left in the environment and utilize bacteria to degrade

the crude oil. This provides a cleanup solution that requires little manpower and can reduce ecosystem disturbances. Currently, National Contingency Plan (NCP) regulation dictates that all sorbents must be removed from oil spills and disposed of properly, but organic loose sorbents can degrade naturally with the oil and should be reconsidered for their sustainable and low-impact properties. Natural sorbents were an unlikely choice during the response effort due to their absence on the product schedule, despite the fact that they are included in Subpart J of the NCP.15

1.6 Fine Assessment in Oil Spill Legislation The existing regulatory framework lacks a robust environmental risk assessment model. The

current legislation that relates most closely to the type of accident experienced in the Gulf consists of the Oil Pollution Act (OPA) and Clean Water Act (CWA). The OPA was established in 1990 in response to the Exxon Valdez oil spill, but is intended to address types of disasters different than that which occurred in the gulf.16 The OPA instituted a cleanup response plan, a funding mechanism in the event of an oil spill disaster and fines geared toward oil pollution. The OPA is built upon principles first enacted in the CWA of 1977. The CWA expanded on prior anti-pollution laws to establish general water quality standards as well as an enforcement plan.17

The OPA holds the responsible party liable for all cleanup costs as well as damages laid out in

seven categories: natural resources, real or personal property, subsistence use, revenues, profits and earning capacity and public services. The CWA also holds the responsible party liable for all cleanup costs but calculates damages differently. One important difference is that the CWA allows a per-barrel fine for oil spills, rather than damages established by experts. These fines can amount to thousands of dollars per barrel of oil spilled and may increase upon cogent evidence of negligence by the responsible party associated with the accident. The OPA and CWA impose liability limits for damage done by an oil spill under most circumstances. Liability under the OPA for the Deepwater

14 Gravois, Kenneth. Louisiana’s Sugarcane Industry. Louisiana Agriculture. Fall 2001. 15 Environmental Protection Agency. “National Contingency Plan (NCP) Subpart J – Product Schedule.” 7 October

2010. http://www.epa.gov/oem/content/ncp/index.htm. 16 Environmental Protection Agency. Oil Pollution Act (OPA). November 21, 2010.

http://www.epa.gov/oem/lawsregs.htm#opa 17 Environmental Protection Agency. Clean Water Act (CWA). November 21, 2010.

http://www.epa.gov/regulations/laws/cwa.html


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Horizon accident is $75 million and $50 million under the CWA. Those liability limits do not apply if the accident was a result of gross negligence. This existing framework effectively addresses large-scale organization, funding, and liability questions but overlooks three critical issues that are particularly relevant to the Deepwater Horizon spill.

The first issue is the release of natural gas that occurred along with the discharge of oil from the

well. An estimated two million oil barrel equivalents of natural gas discharged into the Gulf and had a significant effect on water quality and the Gulf environment.18 Natural gas represented 40% of the hydrocarbons released into the Gulf and should be included in the per-barrel fines under the CWA, as well as the environmental damage analysis required under the OPA.

The second issue is the decision to use chemical dispersants, especially subsea, as a stage 1

response to combat the Deepwater Horizon spill. Approximately 1.8 million gallons of chemical dispersant were released into the Gulf19 and should be included in the environmental impact assessment. While the majority of environmental and economic damage is attributed to crude oil, use of chemical dispersants also may be a contributing factor. By not considering the environmental impacts resulting from decisions to use chemical dispersants instead of oil skimmers, the environmental costs of their use are externalized. If the intent of the OPA and CWA is to hold the responsible parties liable for damage done to the environment, then it is critical to account for all petroleum and other chemical compounds released throughout the oil spill incident.

Third, emissions from in-situ burning and garbage generated from the cleanup need to be

considered in the environmental damage assessment. Eleven million feet of absorbent boom, carcasses, sand/sediment, etc. generated from the cleanup of the Deepwater Horizon event have put an additional burden on landfills. However, most of these waste materials are not accounted for. All waste from cleanup efforts should be accounted for and some may be classified as hazardous substances under the OPA.

2 Looking Forward The Deepwater Horizon Oil Spill was one of the worst environmental disasters in US history

based on the estimated 4.9 million barrels of oil discharged during the 89-day release period.20 Although it is possible to quantify the initial impacts of the event, the true long-term environmental consequences of the catastrophic oil blowout will take time and effort to comprehend. To do so, it is important to identify all variables that directly contribute to the development of a comprehensive assessment, so that all relevant environmental conditions are considered. A comprehensive environmental impact assessment of the Gulf oil spill is important for informing future policy and decision-making related to risk management, fine assessment, and appropriate oil spill response.

Three key components of the Gulf oil spill’s initial environmental impact that have not yet been considered are:

18 Joye, S.B., I.R. MacDonald, I. Leifer, and V. Asper, 2011. Magnitude and oxidation potential of hydrocarbon gases

released from the BP blowout. Nature Geoscience, DOI: 10.1038/NGEO1067. 19 BP. “Dispersant Information.”

http://www.bp.com/sectiongenericarticle.do?categoryId=9034409&contentId=7063742. 20 “Deepwater Horizon MC252 Gulf Oil Budget”, NOAA, August 4, 2010,

http://www.noaanews.noaa.gov/stories2010/PDFs/DeepwaterHorizonOilBudget20100801.pdf.


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• Natural Gas: Natural gas currently is not considered an environmentally

harmful component of the total petroleum discharge. Including methane and other hydrocarbon gases, the total petroleum discharge amounted to more than 6.9 million barrel of oil equivalents, 2 million of which were natural gas.21 The fate of released methane, which biodegrades relatively slowly compared to the other components of natural gas and many liquid hydrocarbons,22 still is unknown.

• Waste Produced: Oily and non-oily waste materials from cleanup efforts are disposed of in local landfills and/or incinerated. These waste materials include 11 million feet of absorbent boom, oil, sand, and sediment from shorelines, marine animal carcasses, personnel materials such as Tyvek suits and gloves, vegetation, and other debris. In addition, after the oil spill recovery operations ended, the response vessels and equipment had to be decontaminated creating additional oily wastewater.

• Response Efforts: Decisions not to prioritize a ‘contain and recover’ protocol most likely will have measurable impacts on the Gulf ecosystem. The toxicity of chemically dispersed oil and chemical dispersants released into the ocean, as well as air pollution resulting from in-situ burning of oil, are additional quantifiable environmental impacts.

The Gulf oil spill response employed three main

technologies—chemical dispersants, in-situ burning, and containment and recovery methods. The latter – which includes absorbent booms, skimmers, and oil-water separators – is environmentally preferable to chemical dispersion or in-situ burning. Oil recovery completely removes oil from the environment and does not increase toxicity to the marine ecosystem. In contrast, chemical dispersion does not remove oil from the water but changes its distribution from the water surface to the water column. The effect of chemical dispersant use on overall toxicity of an oil spill to marine life also is unknown. In-situ burning removes most of the oil, but leaves behind a dense residue which may or may not be possible to collect.23 It also presents an occupational hazard to response personnel due to harmful gases and particulate matter released from the burn. These technologies often are employed simultaneously, as depicted in the graphic to the left,

21 Joye, S.B., I.R. MacDonald, I. Leifer, and V. Asper, 2011. Magnitude and oxidation potential of hydrocarbon gases

released from the BP blowout. Nature Geoscience, DOI: 10.1038/NGEO1067. 22 National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling. "Deep Water: The Gulf Oil

Disaster and the Future of Offshore Drilling." 2011. 23 Office of Response and Restoration. "Open-Water Response Strategies: In-Situ Burning." edited by National Oceanic

and Atmospheric Administration, 1997.


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resulting in a probable decrease in total recovery of oil. For example, surface oil is pooled prior to ignition, meaning it could be skimmed rather than burned. Similarly, applying chemical dispersants at the surface makes skimming which requires a slick of oil, impossible. Applying chemical dispersants at depth, most likely, reduces the amount of oil that reaches the surface and, again, reduces the potential for recovery.

An alternative oil spill response prioritizes containment and recovery as an environmentally

preferable effort throughout successive stages of a spill or discharge. The first stage consists of capturing the oil using containment booms and recovering it with skimmers and absorbent booms�and using natural booms whenever possible to reduce overall environmental waste impact. The second stage, which begins when recovery has reached its maximum capacity and moving oil presents an imminent threat to shoreline ecosystems, utilizes chemical dispersants and in-situ burning where necessary, while continuing containment and recovery. By minimizing chemical dispersant use and in-situ burning, and by prioritizing contain and recover techniques, adverse environmental effects of the cleanup response are minimized.

Current oceanic oil discharge environmental impact assessment is incomplete and inadequate.

The environmental issues discussed in this report are quantifiable and, therefore, should be included in the environmental impact assessment of the Deepwater Horizon oil spill. Looking forward, environmental impact assessments should include the discharge of natural gas, the disposal of waste materials related to the spill and its cleanup, and the environmental impacts of cleanup technologies, such as chemical dispersant application and in-situ burning. Furthermore, no oceanographic science response plan is in place to guide responder strategy, in terms of gathering water column and sediment data. For example, if independent scientists had not discovered the oil plumes and weathered, sedimented oil on the seafloor, those features would not have been documented. By having this data available, these phenomena can be quantified and included in the environmental impact assessment.

The release of natural gas contributes to the adverse environmental impacts of the spill and

should be included in the total petroleum discharge and fined accordingly. The disposal of a significant volume of waste material resulting from the oil cleanup impacts local landfills by introducing oily waste and adding to the overall material burden on solid waste disposal facilities. The material burden on waste facilities can be significantly decreased by selecting sustainable cleanup technologies, such as natural fiber absorbents, which currently are available. The benefits of chemical dispersant application should be weighed against the potential adverse effects. The net result of subsea dispersant use in the Deepwater Horizon spill still is unknown and should be reassessed through controlled research. In-situ burning simply moves oil pollution from the water to the atmosphere, which presents a health risk primarily to response personnel and adds to global stratospheric pollution. These facts argue for containment and recovery of oil to be prioritized whenever possible, and for a reconsideration of a more inclusive environmental impact assessment.

Documents

The Macondo Blowout Environmental Report-DHSG …ccrm.berkeley.edu/pdfs_papers/DHSGWorkingPapersFeb16...Environmental Science, Policy, and Management, University of California, Berkeley