It's rare that oil is spilled intentionally. But that is what recently happened at a lake in Ontario, Canada.
Earlier in June, bitumen -- a molasses-like product that comes from oil sands -- was drizzled into corrals in an unnamed lake in Ontario's International Institute for Sustainable Development Experimental Lakes Area (IISD-ELA). The reason may seem counterintuitive: to protect future freshwater systems from oil spills.
In giant, test tube-like columns of natural lake water, scientists are studying the physical, chemical, biological and toxicological impacts of the diluted form of bitumen (called 'dilbit' for short) on freshwater organisms -- from tiny plankton to frogs and fish.
Until now, these kinds of experiments have only been attempted in the laboratory. But lab-based work can't replicate a real-life scenario.
This experiment, the first of its kind in Canada, is an opportunity for scientists to answer the kinds of questions that could help protect Canada's lakes in the future: What happens to spilled bitumen in freshwater ecosystems? Where does it go? And how can it be cleaned up in the safest, most effective way?
That's because clean up procedures for accidentally spilled dilbit are necessarily different than those for conventional crude oil.
In the weeks leading up to the spill, dozens of students have been labouring at the gravel pit, shovelling sand into bags. They haul their quarry along a muddy, root-filled trail to the lake by lorry and quad bike. Once unloaded, the heavy sandbags are muscled down to the wooden dock to be loaded onto boats.
"It's really cheap cross-fit," says University of Manitoba student Sonya Michaleski, here for her third summer, with a laugh.
Hauling sandbags is one part of her job. Collecting fish slime and fish vomit for analysis is another.
Graduate student Sam Patterson explains his role: drawing water from the enclosures before and after the dilbit spill, then placing the black-dotted eggs of wood frogs in the treated and untreated water to see how the exposure affects their development.
The bulk of the data collection will take place this summer and autumn before the lake freezes up. Subsequent analysis by their team of more than 30 scientists will be shared first in academic journals, but ultimately with the public.
The IISD-ELA is known for its whole lake experiments. Past work has contaminated some lakes with phosphorus, cadmium, mercury, and synthetic oestrogen, the active ingredient in birth control pills. But never oil.
The experiment -- nicknamed Boreal, an acronym for Boreal Lake Oil Release Experiment by Additions to Limnocorrals -- won't be a whole lake experiment, either.
Small enclosures restrict the oil spill area and four extra containment measures are in place to avoid contaminating the entire body of water, explains Vince Palace, IISD-ELA's head research scientist and project leader for a separate oil spill experiment, the Freshwater Oil Spill Remediation Study (Forest).
Still, even this smaller spill area will give scientists a much better idea of how bitumen behaves, and how it affects the environment, than what they are able to mimic indoors in a laboratory.