Petroleum hydrocarbons in the coastal environment

1. Petroleum hydrocarbons in the coastal environment Chris Reddy Dept. of Marine Chemistry and Geochemistry Woods Hole Oceanographic Institution, Woods Hole, MA

2. Petroleum hydrocarbons • Petroleum is the biologic and geologic product of the “cooking and squeezing” of organic matter. • It is composed of many compounds that can have different chemical, physical, and biological properties. • Easiest to class as either refined or crude.

4. Wide-cut gas oils Residual oils Straight-run gasoline Middle distillates 0 0 Kerosine Gasoline fractions 200 Diesel 100 400 Light lubes 200 min max Boiling range °C Light gas oil Heavy lubes Boiling range °F 600 Heavy gas oil 300 400 800 Jet fuel Home heating oil 500 Residuum 1000 600

5. nitrogen, sulfur, and oxygen Boiling point °C 100 200 300 400 500 600 100 normal alkanes 80 branched alkanes cycloalkanes 60 Percentage of molecular types 40 Percentage of molecular types aromatics 20 napthenoaromatics s 0 20 40 60 80 100 Gasoline Heavy Lubricating Kerosene Residuum Diesel gas oil oil fuel

7. Oil in the coastal zone • Urban runofflarge input term “leaky faucet”, mainly used crankcase oil from cars and trucks, relatively low acute toxicity, impacts urban areas. • Oil spillssmaller input, but is a dramatic event that may be from a wide range of products, toxicity can vary, pristine areas are vulnerable. • Natural oil seepslarge input for long times scales, crude oil with varying toxicity.

8. Why study the fate of oil? • Excellent opportunity to observe how ecosystems react to anthropogenic perturbations. • Use knowledge for “engineered” clean-ups. • Societal issues (human and animal health) • Oil Pollution Act of 1990

9. Historical Spills Bouchard 65 Winsor Cove October 9, 1974 41,000 to 140,000 L of diesel fuel Florida Wild Harbor September 16, 1969 Spilled 700,000 L of diesel fuel

10. Florida spill: Background • On September 16, 1969, the barge Florida ran aground on rocks near West Falmouth, MA. • Over ~650,000 liters of diesel fuel spilled into the water column. • Storm winds from the southwest drove the oil into Wild Harbor.

13. Florida spill (1969) Concentration of total petroleum hydrocarbons (TPHs) (mg g-1 dry weight) 0 2 8 4 6 10 0 5 10 15 Depth (cm) 20 25 30 Wild Harbor August 2000 35 40

15. Atlantic marsh fiddler crab Uca pugnax

16. Burrowing depth Made plaster casts of burrows in areas of Wild Harbor and Great Sippewissett to compare burrow depths of oiled and non-oiled areas.

17. Peacock et al. 2005

18. RESULTS: Burrowing depth Significant difference between oil and non-oil areas in Wild Harbor (t-test, p < 0.001)

19. Burrow casts Great Sippewissett Wild Harbor (oiled)

20. Florida spill (1969) Concentration of total petroleum hydrocarbons (TPHs) (mg g-1 dry weight) 0 2 8 4 6 10 0 5 10 15 Depth (cm) 20 25 30 Wild Harbor August 2000 35 40

23. Santa Barbara Oil Seeps • Releases >20,000 liters of petroleum daily. • Seepage has been occurring for thousands of years. • Sheens and tar balls along the Santa Barbara coastline are constant reminders of this natural process. • Excellent opportunity to study the fate of petroleum in the marine environment. • My group started work at this site a few months ago.

27. Seep stringer

28. Tarballs

29. Holly Platform product

30. Santa Barbara seep stringer

31. Santa Barbara beach tar

32. Santa Barbara beach tar

33. Summary • Oil can have different properties and behave differently in the environment. • Thanks to Helen White, Bob Nelson, Greg Slater, Jennifer Culbertson, Ivan Valiela, and Emily Peacock