Effects of Chemically Dispersed and Biodegraded Oils

Principal Investigator: Dr. Steve Rowland, Plymouth Laboratories, Inc.

Estimated Completion: July 2005

This project will determine the effects of chemically dispersed and biodegraded oils. Research will provide a quantitative assessment of the rate of biodegradation of the components under a range of conditions found in the UK and cold US waters. This information will be useful to decision makers when choosing appropriate response options/strategies. The UK partners are the Maritime and Coast Guard Agency, the Department of the Environment for Rural Areas, and the Department of Trade and Industries.

In 2003, MMS had Alaska North Slope crude oil and Corexit 9527 dispersant shipped from the Ohmsett facility to Plymouth laboratory in the UK. The UK government supplied Forties crude oil and SuperDispersant 25. Plymouth labs conducted laboratory analyses using the both crude oils and dispersants. Mussels and mud shrimp were used in toxicity tests. Results from this project were made at the 15th annual The Society of Environmental Toxicology and Chemistry (SETAC) conference in Lille, France on May 23, 2005. The final project report is being reviewed by MMS.

Correlate Ohmsett Dispersant Tests with At Sea Trials; Supplemental Tests to Complete Test Matrix

Principal Investigator: Dr. Ken Trudel, S.L. Ross Environmental Research, Ltd.

Estimated Completion: July 2005

In October 2003, MMS sponsored a project at Ohmsett - The National Oil Spill Response Test Facility entitled: "Correlate Ohmsett Dispersant Tests with At-Sea Trials". The primary objectives of this project were achieved however due to time constraints and adverse weather some important experiments in the test matrix could not be performed. The objectives of this work is to conduct a small number of tests to complete two important sections of the dispersant effectiveness (DE) test matrix, thereby solidifying our understanding of the correlation of Ohmsett DE testing to at-sea DE testing. These objectives are:

• Conduct replicated measurements of dispersant performance at Ohmsett under a number of oil-dispersant-DOR conditions that yielded high levels of dispersion at sea.
  
  
• Conduct control runs for both test oils IFO-180 and IFO-380 fuel oils at both wave frequencies (30 and 33.3 cpm).
  

These experiments were completed in April 2005. The final project report is being reviewed by MMS.

Dispersant Effectiveness Testing on Heavy Outer Continental Shelf Crude Oils at Ohmsett- The National Oil Spill Response Test Facility

Principal Investigator: Mr. Randy Belore, S.L. Ross Environmental Research, Ltd.

Estimated Completion: July 2005

This project will determine the limiting viscosity for the effectiveness of chemical dispersants applied to viscous U.S. Outer Continental Shelf (OCS) crude oils from the Gulf of Mexico and Pacific.

• Nine crude oils were identified and three barrels of each crude oil were procured for testing.
  
  
• Physical and chemical analysis of the acquired crude oils was conducted to categorize them based on properties.
  
  
• Small-scale wave tank dispersant effectiveness (DE) were conducted in February 2005 on nine crude oils. Corexit 9500 dispersant was applied at the standard 1:20 dispersant to oil ratio (DOR).
  
  
• Large-scale wave tank DE experiments were conducted on the crude oils at Ohmsett - The National Oil Spill Response Test Facility from April 18-30, 2005. A visitor's day held on April 19, 2005 attended by scientists, spill responders and regulators to observe the DE experiments.
  
  
• MMS invited the U.S. Coast Guard, Atlantic Strike Team, the Environmental Protection Agency/ Emergency Response Team to use the experiments as an operational training exercise for the SMART dispersant monitoring protocol.

The final project report is being reviewed by MMS.

Laboratory Testing to Determine Dispersion Predictability of the Baffled Flask Test and Swirling Flask Test

Principal Investigators: Dr. Albert Venosa, U.S. Environmental Protection Agency and Dr. George Sorial, University of Cincinnati

Estimated Completion: July 2005

This project will conduct standardized laboratory dispersant effectiveness (DE) testing to determine if either the Baffled Flask Test (BFT) or the Swirling Flask Test (SWT) is able to predict the DE of oil spills similar to what was experienced in the field during the UK at-sea trials and at Ohmsett - The National Oil Spill Response Test Facility during the large-scale DE experiments.

DE experiments was conducted using the BFT and SWT test protocols with three dispersants (Corexit 9500, SuperDispersant 25 and Agma DR 379), two fuel oils (IFO-180 and IFO-380), at one dispersant to oil ratio (DOR 1:25) and at one temperature (16 o C). This amounted to twelve experiments (each with four replicates) for a total of forty-eight DE experiments. Additional experiments were run at the 20o C.

Testing is complete and the U.S. EPA/University of Cincinnati is preparing the final project report.

The Effect of Warming Viscous Oils Prior to Discharge on Dispersant Performance

Principal Investigator: Mr. Randy Belore, S.L. Ross Environmental Research, Ltd.

Estimated Completion: September 2005

Large-scale wave tank experiments were conducted in 2002 and 2003 at Ohmsett - The National Oil Spill Response Test Facility to assess the dispersibility of fresh and weathered Alaskan and Canadian crude oils in very cold water. Results from these experiments indicate that the crude oils tested were dispersible at near freezing water temperatures. However, there has been criticism of the findings related to the warming of the viscous oils prior to their discharge onto the waters surface and subsequent dispersant application. This project will address criticism of dispersant testing at Ohmsett. The experiments will determine empirically whether heating viscous crude oils prior to testing influences dispersant performance in Ohmsett tests.

The project will repeat certain Ohmsett experiments using unheated oil to determine whether the effect of preheating the oil is large enough to alter the overall conclusions of the original dispersant effectiveness experiments conducted in 2002 and 2003. Specifically this work will:

• Determine the rate of cooling of slicks formed by discharging heated crude oil on cold seawater.
  
  
• Compare the dispersibility of oils that are heated prior to discharge against oils discharged at ambient temperatures.
  
  
• Experiments will be conducted in September 2005.
  

Analysis of Dispersant Effectiveness of Heavy Fuel Oils and Weathered Crude Oils at Two Different Temperatures Using the Baffled Flask Test

Principal Investigators: Dr. Albert Venosa, U.S. Environmental Protection Agency and Dr. George Sorial, University of Cincinnati

Estimated Completion: September 2005

At-sea dispersant effectiveness (DE) experiments were conducted in the summer of 2003 in the UK and large-scale wave tank experiments were conducted in the fall of 2003 at Ohmsett - The National Oil Spill Response Test Facility to determine the dispersibility of IFO-180 and IFO-380 fuel oils. In 2004 additional DE testing on these fuel oils was conducted at laboratory scale and in small wave tanks. The Minerals Management Service (MMS), ExxonMobil, the Canadian Department of Fisheries and Oceans and CEDRE in France funded these experiments.

In FY-2004, MMS funded the U.S. Environmental Protection Agency (US EPA) and their on-site cont/ractor the University of Cincinnati to conduct laboratory DE testing using two test protocols the Baffled Flask Test (BFT) and the and Swirling Flask Test with three dispersants (Corexit 9500, SuperDispersant 25 and Agma DR 379), two fuel oils (IFO-180 and IFO-380), at one dispersant to oil ratio (DOR 1:25), and at one temperature (16oC). This amounted to twelve experiments (each with four replicates) for a total of forty-eight DE experiments.

Results from this project were used to prepare several scientific papers for the 2005 International Oil Spill Conference. During peer review of the scientific papers, data gaps were identified that need to be filled in order to get a more complete correlation between laboratory testing, small and large wave tank testing and at-sea field trials. This research project will address these data gaps.

• This project is an Interagency Agreement equally funded by the U.S. EPA and MMS.
  
  
• UC will conduct standardized laboratory DE testing to determine if the BFT is able to predict the DE of oils similar to what was experienced during the UK at-sea trials and at Ohmsett.
  
  
• A secondary objective is to determine how closely results from the BFT match with results obtained from the UK at-sea trials and at Ohmsett.
  

Calm Sea Application of Dispersants

Principal Investigator: Dr. Ken Trudel, S.L. Ross Environmental Research Ltd. and Randy Belore, S.L. Ross Environmental Research Ltd.

Estimated Completion: December 2005

The objective of this project is to determine the period of time that oil spill dispersants applied to spilled oil in a calm sea will remain effective before the sea state increases and dispersion occurs.

• Identify Outer Continental Shelf (OSC) crude oils and a marine fuel oil for testing.
  
  
• Assess dispersibility of these oils when fresh and weathered for 12, 24 and 48 hours.
  
  
• Select two OCS crudes, the PERF** oil (Sture Blend) and the marine fuel for testing at small-scale.
  
  
• Conduct small-scale testing to determine length of time that oils remain dispersible if sprayed with dispersant and allowed to sit in calm water for 0, 12, 24 and 48 hours before being agitated with cresting waves.
  
  
• Conduct large-scale testing with one OCS crude oil, the PERF oil and the fuel oil under near-at-sea conditions at Ohmsett - The National Oil Spill Response Test Facility to determine length of time that oils remain dispersible if sprayed with Corexit 9500 dispersant and allowed to sit in calm water for 0, 12, 24 and 48 hours before being agitated with cresting waves.
  
  
• The dispersant effectiveness experiments were conducted at Ohmsett from June 27-July 15, 2005.

**Related work is planned in an ExxonMobil sponsored project coordinated under the Petroleum Environmental Research Forum (PERF). Every effort is being made to coordinate the present study with PERF work.

Chemical Dispersibility of OCS Crude Oils in Non-Breaking Waves
Part 1: Determining the Limiting Oil Viscosity for Dispersion in Non- Breaking Waves

Principal Investigator: Dr. Ken Trudel, S.L. Ross Environmental Research Ltd.; Mr. Randy Belore, S.L. Ross Environmental Research Ltd.; and Mr. Alun Lewis, Alun Lewis Oil Spill Consultancy

Estimated Completion: December 2005

Project will determine whether chemically treated low-viscosity, low pour point crude oils disperse in a non-breaking wave environmental and if so, to determine whether there is a limiting oil viscosity for chemical dispersion for OCS crude oils in non-breaking waves. The project objectives are to:

• Identify and procure six Outer Continental Shelf crude oils for testing.
  
  
• Conduct small-wave tank dispersibility experiments on six crude oils using low-amplitude non-breaking waves to determine:
  
  
  1. Whether any of these oils is chemically dispersible under non-breaking wave conditions.
     
     
  2. If there is a threshold limiting oil viscosity for chemical dispersible under non-breaking wave conditions.
     
     
  3. Whether dispersion is limited because the wave energy is not sufficient to over come the visco-elasticity of the oil or because in water mixing energy is insufficient to keep the dispersed oil droplets of low-density oil in suspension.
     
     
• Large-scale dispersibility experiments on four selected crude oils were conducted at Ohmsett - The National Oil Spill Response Test Facility from July 18 - August 5, 2005.

Dispersant Effectiveness Testing on Realistic Emulsions at Ohmsett - The National Oil Spill Response Test Facility

Principal Investigator: Mr. Randy Belore, S.L. Ross Environmental Research, Ltd.

Estimated Completion: April 2006

This project will determine the viscosity limit for the effective application of chemical dispersants to realistic emulsions. The project objectives are to:

• Conduct small-wave tank experiments to confirm that the crude oils selected for use in this project will form stable emulsions.
  
  
• The preliminary effectiveness tests will provide information for determining the testing order of the emulsions. Tests where effectiveness is expected to be poor will be conducted first to prevent tank fouling for subsequent tests.
  
  
• Conduct dispersant effectiveness experiments on the emulsions at Ohmsett - The National Oil Spill Response Test Facility from December 5-16, 2005 using Corexit 9500 and Corexit 9527 dispersants.

Laboratory Study of the Effects of Time on the Effectiveness of Dispersants

Principal Investigator: Dr. Per Daling, SINTEF Materials and Chemistry

Expected Completion: September 2006

ExxonMobil has formed a Joint Industry Project with Alaska Clean Seas, Agip, Kazakhstan North Caspian Operating Company, the Minerals Management Service, Oil Spill Response Limited, Statoil, Sakhalin Energy Investment Company to determine whether dispersants will remain with treated oil slicks over time and retain effectiveness. This would make it possible to apply dispersants to oil slicks under low energy conditions and have them remain with the oil until the energy level increases to a point where dispersion into the water column occurs. This study will be conducted by SINTEF in Norway and CEDRE in France. Project tasks are:

• Literature Review: Prepare a summary of prior related work on the fate of dispersants in contact with oil and water over time and the effect of oil viscosity/weathering on dispersant effectiveness. This is to document the body of knowledge on the subject to avoid repeating research.
  
  
• Fate of Dispersants Over Time (without freezing): Evaluate to the extent to which dispersant stays with the oil and remains effective over time as a function of various oil types/oil weathering, and sea temperatures. Determine conditions under which slicks could/may spontaneously form micron sized oil droplets during prolonged exposure.
  
  
• Fate of Dispersants Over Time (with freezing): Evaluate the extent to which dispersant stays with the oil and remains effective over time, through freezing into an ice layer and spring migration through the ice layer to the surface as the ice thaws.
  
  
• A progress meeting was conducted on July 8, 2005 in Trondheim, Norway to review results of literature review and the initial results from dispersant testing.

Cold Water Dispersant Effectiveness Experiments on Alaskan Crude Oils at Ohmsett - The National Oil Spill Response Test Facility

Principal Investigator: TBD

Estimated Completion: September 2006

Based on recommendations from the National Academy of Science report (pp. 57-58), the Minerals Management Service (MMS) plans to repeat the 2002 and 2003 cold water dispersant effectiveness (DE) experiments conducted at Ohmsett - The National Oil Spill Response Test Facility using the improved oil distribution system that does not require warming of the heavy viscous crude oils. Three weeks of cold water (DE) experiments will be conducted at Ohmsett from March 13-30, 2006 using Alaskan crude oils.

Mid-Scale Tank Research Using Oil Herding Surfactants to Thicken Oil Slicks in Broken Ice

Principal Investigator: Mr. Ian Buist, S.L. Ross Environmental Research, Ltd.

Estimated Completion: January 2007

The Minerals Management Service (MMS) and ExxonMobil has formed a Joint Industry Project to continue research on the use of chemical herding agents to thicken oil spills in broken ice that will allow them to be effectively ignited and burned. ExxonMobil funded the initial laboratory experiments and small-scale tank tests. Three full-scale experimental programs will be conducted.

• Late Fall 2005 - Conduct a series of research experiments on the efficacy of herders to thicken oil slicks among broken ice at sub-zero temperatures. Tests will be conducted at the scale of 100 m2 US Army Cold Regions Research and Engineering Laboratory in Hanover, NH.
  
  
• January-February 2006 - Conduct a series of research experiments on the efficacy of herders to thicken oil slicks among broken ice at sub-zero temperatures. Tests will be conducted at the scale of 1000 m2 at Ohmsett - The National Oil Spill Response Test Facility. The Ohmsett experiments will be conducted in conjunction with the MMS Alaska Environmental Studies Program oil spreading and emulsification experiments in broken ice already scheduled for the winter 2006.
  
  
• October 2006 - Conduct a series of in situ burn experiments on the scale of 50 m2 with chemical herders and crude oil at the Fire Training Grounds, Prudhoe Bay, AK. The burns would be conducted in a specially prepared pit containing broken sea ice.

Workshop to Determine the Scope of an Experimental Oil Spill in Pack Ice in Halifax, Canada, November 1-2, 2005

Principal Investigator: Mr. Steve Potter, S.L. Ross Environmental Research, Ltd.
Mr. David Dickins, DF Dickins and Associates

Estimated Completion: April 2006

The objective of this project is to conduct a planning workshop for an experimental oil spill in pack ice offshore Canada in 2007. Dr. Ken Lee, Department of Fisheries and Oceans Canada, will co-fund the workshop with the Minerals Management Service (MMS). Specifically this work will:

• Prepare a background information document for the proposed workshop;
  
  
• Plan the workshop;
  
  
• Facilitate the workshop; and
  
  
• Write a report on the results of the workshop.

The workshop is tentatively scheduled for November 1-2, 2005 at the Bedford Institute of Oceanography, Halifax, Nova Scotia. An invitation and information package is being developed, and will be sent to a limited list of government, industry, academic, and environmental groups around the world with an interest in oil spill research in cold waters. The planned spill would be in 2007 to coincide with the International Polar Year. The MMS is involved in a similar effort being planned for a spill offshore Norway as well in 2007.