FROM OIL TO SOIL: journey from chemical impediment to pristine sediment in a few “easy” steps
OR How to clean up the ecosystem (eventually)
Part 1: Uh oh
Prologue: the TC Energy “oopsie”
Dec 7th: a pipeline in rural Kansas bursts, releasing hundreds of thousands of gallons of crude petroleum and into Mill Creek.
From NPR: “The spill in Kansas is now the second-largest spill of tar sands crude on U.S. soil. And scientists say this stuff comes with major complications for containing and cleaning it.“
Not just oil, its dilbit (not Dilbert in Lucy’s accent) aka diluted bitumen
“... the pipeline that busted just outside the town of Washington on Dec. 7 doesn’t carry conventional crude oil. It carries a product of the Canadian tar sands called diluted bitumen that changes dramatically in chemical composition and behavior soon after escaping from pipes.
A National Academies of Sciences study found that transformation means the crude oil can start sinking below the water’s surface in a matter of days.“
Texas tea
Black gold
Fort worth shampoo
But what is it?
Petroleum, also known as crude oil, or simply oil, is a naturally occurring yellowish-black liquid mixture of mainly hydrocarbons,[1] and is found in geological formations. The name petroleum covers both naturally occurring unprocessed crude oil and petroleum products that consist of refined crude oil. A fossil fuel, petroleum is formed when large quantities of dead organisms, mostly zooplankton and algae, are buried underneath sedimentary rock and subjected to both prolonged heat and pressure.
Why is it bad for us if it looks so tasty
“[oil contains] volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs). In terms of how long they remain in the environment, they represent two ends of a spectrum. All crude oil contains VOCs, which readily evaporate into the air, giving crude oil a distinctive odor. Some VOCs are acutely toxic when inhaled, in addition to being potentially cancer-causing. At the site of a fresh oil spill, these VOCs can threaten nearby residents, responders working on the spill, air-breathing marine mammals, and sea turtles at the water surface. However, VOCs are generally a response concern only right after oil is spilled, because oil floating on the sea surface quickly loses its VOCs.In contrast, PAHs can persist in the environment for many years, in some cases continuing to harm organisms long after the oil first spills. How PAHs in oil do that is an active area of research...”
“When oil washes ashore, it can completely cover and smother the plants and animals living there. Crude oil not only destroys the insulating properties of animal fur and bird feathers, which can lead to hypothermia, but it also impairs animals' abilities to fly and swim, sometimes causing oiled animals to drown…”
So you’ve gone and spilled some, have you
How much?
Oh shit, that’s a lot. Where’d you spill it?
Not in a body of water, surely?
You spilled it in the ocean… fuck… it’s all over the birds… if only we could spray some sort of dispersant…
Heads up asshole, the dispersant’s toxic too
Macaulay et al. 2013
Teal and Howarth 1984
ENTER THE MICROBE
If it’s got redox potential….the ‘crobes will eat it… so long as there’s oxygen
Oil accumulates in sediments
From wiki: Chemical solvents and dispersants were briefly used by Exxon in water surrounding the Valdez although discontinued as they required specific conditions and contained carcinogenic compounds.[12] Bioremediation techniques used in the Exxon Valdez spill included nitrogen and phosphorus seeding along coastline increasing available nutrients for indigenous petroleum degrading microorganisms doubling rates of decomposition.[13] Across all remediation techniques less than ten percent of the oil released from Exxon Valdez tanker was recovered.[12] Many genera of plant, microbes, and fungi have demonstrated oil remediating properties including Spartina, Haloscarcia, Rhizophora, Nocardioides, Dietzia, and Microbacterium.[14][15][16][17]
Now what do we do?
ENTER: the engineers (sediment macrofauna)
Apocorophium sp.
“We hypothesize that amphipod grazing increased the
supply and/or availability of microalgae to surface- and suspension-feeding invertebrates either by stimulating microalgal
primary production or by suspending microalgal particles, or both”
It may be a while…
A time series of coral showing the progression of typical impacts at a site of coral colonies located less than seven miles from the source of Deepwater Horizon oil. You can see the brown "floc" material present in November 2010 disappears by March 2011 and afterward, is replaced by fuzzy gray hydroids and the coral loses its brittlestar companion. (Credit: Hsing et al. 2013
)
A Long Time Coming
Life on the bottom of the ocean moves slowly. Deep-sea corals live for hundreds to thousands of years, and their deaths are rare events. Some of the corals coated in oily brown floc are about 600 years old (Prouty et al. 2014
). The observed impacts to life in the deep ocean are tied closely to the Deepwater Horizon oil spill, but the full extent of the harm and the eventual recovery may take years, even decades, to manifest (Fisher and Demopoulos, et al. 2014
).
Worse in the global south: Macaulay et al 2013
References:
Fleeger, J. W., Johnson, D. S., Zengel, S., Mendelssohn, I. A., Deis, D. R., Graham, S. A., Lin, Q., Christman, M. C., Riggio, M. R., & Pant, M. (2020). Macroinfauna responses and recovery trajectories after an oil spill differ from those following saltmarsh restoration. Marine Environmental Research, 155, 104881.
Fleeger, J. W., Johnson, D. S., Zengel, S. A., Mendelssohn, I. A., Deis, D. R., & Graham, S. A. (2022). A macroinfaunal ecosystem engineer may facilitate recovery of benthic invertebrates and accompanying ecosystem services after an oil spill. Estuaries and Coasts, 45(2), 582–591.
Le Hir, M., & Hily, C. (2002). First observations in a high rocky-shore community after the Erika oil spill (December 1999, Brittany, France). Marine Pollution Bulletin, 44(11), 1243–1252.
Macaulay, B. M., & Rees, D. (2014). Bioremediation of oil spills: a review of challenges for research advancement. Annals of Environmental Science, 8, 9–37.
Pérez-del-Olmo, A., Raga, J. A., & Kostadinova, A. (2022). Parasite communities in a marine fish indicate ecological recovery from the impacts of the Prestige oil-spill 12–13 years after the disaster. Science of The Total Environment, 847, 157354.
Rivera-Parra, J. L., Vizcarra, C., Mora, K., Mayorga, H., & Dueñas, J. C. (2020). Spatial distribution of oil spills in the north eastern Ecuadorian Amazon: A comprehensive review of possible threats. Biological Conservation, 252, 108820.
Teal, J. M., & Howarth, R. W. (1984). Oil spill studies: a review of ecological effects. Environmental Management, 8(1), 27–43.
Zengel, S., Bernik, B. M., Rutherford, N., Nixon, Z., & Michel, J. (2015). Heavily Oiled Salt Marsh following the Deepwater Horizon Oil Spill, Ecological Comparisons of Shoreline Cleanup Treatments and Recovery. https://doi.org/10.1371/journal.pone.0132324