When Spilled Oil Does Not Float: Challenges of Finding, Tracking, and Recovering It Jacqueline Michel, Ph.D. Research Planning, Inc./Univ. of New Orleans

Why Increase in Non-floating Oil Spills? Residual oils are heavier (now 7% vs 12% of a barrel of crude oil) Cutter stocks used for blending are heavier Utilities looking for lowest costs Only requirements are viscosity and BTU

Properties of Heavy Oils API Gravity 0.98 Pour point is not always high because of low parrafin content Often remain liquid initially after spillage Become highly viscous when emulsified

Heavy Oil Issues Do not fit standard models for oil behavior and fate Often will float initially, then partially sink or become neutrally bouyant Techniques for location, containment, and recovery of non-floating oils very limited

HEAVY

Models for Heavy Oil Behavior Model 1 - Majority floats Model 2 - Majority does not float Model 3 - Majority floats initially, but then some of it does not float after picking up sediment (sand)

HEAVY

Spills Where Oil Sank Initially SS Sansinena, Los Angeles Harbor, California, API = 7.9 (sank) T/B MCN-5, Puget Sound, Washington, API = -1.0 (suspended) T/S Mobiloil, Columbia River, Oregon, API = 5.4 (suspended)

Oil Sank After Stranding Onshore IXTOC 1, South Texas, Heavy Mexican crude - tarmats at toe of beach T/V Alvenus, Galveston, Texas, Heavy Venezuela crude - tarmats in offshore bars T/V Haven, Genoa, Italy, Heavy Iranian crude, weathered and burned oil residues formed tarmats off sand beaches

Oil Sank After Stranding Onshore T/V Prestige, Spain, Heavy fuel oil – unknown amount of oil was deposited on seafloor near vessel and close to shore T/V Athos, Delaware River, Heavy Venezuela crude - suspended oil in river after stranding on sand flat

Oil Sank After Picking Up Sand Offshore T/B Bouchard-155, Tampa, Florida, Heavy fuel oil - API = 10.5 T/B Morris J. Berman, Puerto Rico, Heavy fuel oil - API = 9.5

HEAVY

Oil Sank after Extreme Heating or Burning T/V Haven, Genoa, Italy, 1991 T/V Haven, Genoa, Italy, Heavy Iranian crude oil, heated onboard during fire, distilled light components Honam Jade, South Korea, 1983 Honam Jade, South Korea, Floating slicks burned, sank nearby, contaminating crab pots

Conclusions on Floaters that Don’t Only heavy crude or fuel oils are at risk Only heavy crude or fuel oils are at risk There are two primary mechanisms for floating oils to later “sink”: There are two primary mechanisms for floating oils to later “sink”: Incorporation of sand, either onshore or offshore Incorporation of sand, either onshore or offshore Extreme loss of the volatile fractions after heating or burning Extreme loss of the volatile fractions after heating or burning

Types of Non-Floating Oil Pooled oil: Pooled oil: Accumulated in depressions and not mobilized by normal tidal and riverine currents Mobile oil: Mobile oil: Negatively buoyant but subject to transport by tidal and riverine currents (NO containment possible!)

Pooled Oil Detection Methods Visual observations/photography (clear water) Bottom sampling from the surface (cores, sorbent drops/drags/trawls) Geophysical/acoustic techniques Underwater diver surveys Search natural accumulation areas

Mobile Oil Detection Methods Sonar systems Water sampling Fish net trawls Snare samplers Vessel-Submerged Oil Recovery Systems (V-SORS)

Snare sampler Locations Delaware River

Interpolated Snare Sampler Data 8-10 Dec 2004 Reds = >10% Yellows = 1-10% Light Green = <1%

Interpolated Snare Sampler Data Dec 2004 Reds = >10% Yellows = 1-10% Light Green = <1%

Interpolated Snare Sampler Data Dec 2004 Reds = >10% Yellows = 1-10% Light Green = <1%

8-10 Dec 2004 Reds = >10% Yellows = 1-10% Light Green = <1% Dec Dec 2004

Pooled Oil Recovery Surface-supplied diver operations Specialized viscous oil pumping systems Large volume water decanting system Recovered oil may float or sink Lots of trial and error, learning, refinement

Athos 1 Nov 2004

T/B Morris J. Berman, Puerto Rico, 1993

Research Recommendations: Non-floating Oils 1. Develop better understanding of behavior and fate on non-floating oil spills Behavior when suspended by currents Improve modeling of suspended oil transport Predict weathering processes of pooled oil on the seafloor

Research Recommendations: Non-floating Oils 2.Develop effective remote sensing techniques to detect/track Oil suspended in the water column Oil pooled on the seafloor

Research Recommendations: Non-floating Oils 3.Have more international coordination on non-floating oil issues Oil spill research $$ is low (US = $10 million) Experience is very emperical, so need to learn from every spill See recommendations in NRC (1999) – “Nonfloating Oil Spills: Risks and Response” at

Potentially Polluting Wrecks (PPW) Recent catastrophic losses of vessels (e.g., Prestige, Erika) Increasing risks of oil releases from relic wrecks Result: Result: Increased demands to remove all pollutants from submerged wrecks Issue: Issue: Proactive or Reactive?

Goals of 2005 International Oil Spill Confernce Issue Paper Provide an objective analysis of current state and risks of potentially polluting wrecks in marine waters, and Identify considerations for future actions

PPWs: How Many/Where? Obtained all available databases, e.g., NOAA RUST SPREP NOAA AWOIS Lloyd’s Casualty Archive Lloyd’s Maritime Casualties German World War II Maritime Shipwrecks

CRITERIA FOR INCLUSION: Marine waters Petroleum-based oil or oil products Non-tank vessels > 400 gross tonnage Tank vessels > 150 GT Not reported as raised, salvaged, lightered, or scrapped PPWs: How Many/Where?

RESULTS: 1,583 tank vessels (including barges) 6,986 non-tank vessels Total of 8,569 PPWs Dates range from 1890 to % of all vessels are World War II incidents ( )

November 20, U.S. personnel killed 12,900 t of oil loaded Sunk in 40 m Sinking of USS Mississinewa

Numbers of Potentially Polluting Wrecks >300 wrecks

PPWs: How Much Oil? HIGH ESTIMATE: Tankers had 80% cargo capacity onboard (unless reported as being in ballast) Cargo volume based on DWT or net tonnage Bunkers were 70% full

Low Estimate

Low Estimate Leak Loss Erika loss = 64 % of cargo Prestige loss = 83 % Yu II No. 2 loss = 78 % Osung No. 3 loss = 99 % AVERAGE = 83 %

Vessel Type Type Number of Vessels Number of Vessels High Estimate High Estimate Low Estimate Low Estimate Tank Vsl >150 GT 1, x10 9 gal; 14.6x10 6 t 0.5x10 9 gal; 1.8x10 6 t Non-tank Vsl >400 GT 6, x10 9 gal; 5.8x10 6 t 0.2x10 9 gal; 0.7x10 6 t Total8,569 6x10 9 gal; 20.4x10 6 t 0.7x10 9 gal; 2.5x10 6 t

Potential Volume of Oil in Wrecks >500,000 t 100, ,000 t 50, ,000 t 10,000-50,000 t 1,000-10,000 t 1-1,000 t

Future Considerations 1.Conduct systematic risk assessments -Coordinated regionally -Identify wrecks that pose greatest risks 2.Adopt the IMO DWRC and include financial responsibility for wreck removal 3.Design vessel with emergency piping for oil removal

Future Considerations (cont.) 4.Research corrosion rates 5.Research heavy oil properties (high pressure, cold water) 6.Develop non-destructive oil sensing technology 7.Improve methods to reduce oil viscosity