Here are a few tips on telling the difference between naturally occuring oily sheens on water and petroleum-based ones.
How to tell the difference between petroleum sheens and organic ones:
- Take a whiff. Bacteria-based, organic sheens don't have that distinct gas or diesel smell. They are often "humic" sheens caused by bacteria. (Humus is the organic compound in soil formed by decaying plant matter.)
- Look around. Is there an obvious source of petroleum that could have caused the sheen? Bear in mind, heavy rains often cause runoff from roads, parking lots and sidewalks.
- Poke the stuff. Break the oily surface of the water with a stick or a stone and watch what happens. If the sheen breaks up into platelets, it's probably natural. If the material tries to reform and moves back together to close the gap, then it's likely petroleum.
What to do:
- If you suspect the material is harmful to the environment, take pictures or video if you have smartphone or camera and be sure to show the surrounding area for context to indicate where the spill occurred.
- For Burnaby spills, call the city immediately at 604-294-7200. (In Vancouver, call 311.) The provincial emergency program has a 24-hour hotline for oil and hazardous material spills: 1-800-663-3456.
- After you've alerted authorities, call your local environmental reporter, Jennifer Moreau, at 604-444-3021. Reporting on these issues helps hold polluters accountable.