With my daughter and two granddaughters aboard, I paddled my canoe through the Rotary Club’s artificial pond near the Southshore Centre on Thursday, Aug. 11.
The small girls laughed at all the ducks, but we hushed them so we could creep up on an elegant great blue heron less than two metres away.
Then we paddled out into Kempenfelt Bay and on to Minet’s Point Beach where the girls could play.
On the morning of Saturday, Aug. 13, my buddy and I launched our rowing boat from the Barrie Rowing Club’s dock.
We did our usual circuit — to the north shore, east to Johnson’s Beach, then across the bay to Brentwood Marine and finally returning to the dock. When we arrived at the dock, we could smell a pungent odour of diesel fuel.
You could see a flickering rainbow sheen on the water, as if you had spilled some outboard fuel.
It was clear that the ducks had wisely deserted the pond. The City of Barrie had cleaned up most of it, set out cloth barriers to contain the spill, and spread out special blue cloth to absorb as much of fuel residue as possible. The cloth used is quite similar to the J-Cloth you may use to wipe kitchen counters.
Spills may harm aquatic life. Bird feathers are naturally oily to keep them dry in the rain, but swimming through a fuel spill can wash away this oil, leaving birds susceptible to cold as their feathers lose their insulating properties. The feathers of an oiled-exposed bird are often useless for flight, which makes them vulnerable to predators.
Although these liquid fuels are lighter than water, so they float on the surface, they can harm fish and other aquatic animals. If a fish surfaces, swimming through the floating fuel could expose their gills, affecting their ability to transfer oxygen. The fish could then suffocate and die. The same applies to other aquatic animals such as frogs, salamanders, shrimp, etc.
This was a small spill in Barrie. Originally, it smelled nasty, but a few days later there is little odour and just a slight oily sheen on the water near the Barrie Rowing Club’s dock.
Nobody has yet been identified as responsible for the spill. Any gas stations reasonably close to the spill would have drained into the sewage outfalls on either side of the Southshore Centre. But these are not how the fuel reached the artificial pond.
Speculation at this point is not helpful. What is important is that the city dealt with the spill promptly. The Ministry of the Environment, Conservation and Parks has samples and will try to identify where it came from.
The cleanup, meanwhile, has cost the City of Barrie around $50,000, and citizens like myself would like the culprit pay that bill.
People who are only interested in the spill can stop reading here. For others, below is a description of how petroleum came to be formed.
Petroleum is formed from the remains of small animals which lived and died in warm, shallow seas. Deeply buried under countless layers of sediment for millions of years, this organic matter decomposed slowly driving off carbon dioxide, methane and other gases. This process left behind a solution of highly pressurized gaseous, liquid and some solid hydrocarbons.
The process was hugely inefficient. Just a tiny percentage of the original biomass becomes petroleum. Each litre of gasoline came from 24 tonnes, an 18-wheeler’s cargo, of original living biomass.
There are many places on Earth where petroleum has been found, including Saudi Arabia, Iran, Nigeria, Algeria, Venezuela, Russia, Angola, plus various parts of the United States and Canada. These days, Canada’s major petroleum resource comes from Alberta’s and Saskatchewan’s “tar sands.”
To become liquid petroleum, the original biomass must eventually be “capped” by impermeable rock. This rock prevents the escape of the carbon dioxide, methane and other gases. It also prevents evaporation of the hydrocarbon liquids.
This didn’t happen in the tar sands. As a result, the gas components and most of the liquids were lost leaving sand held together by semi-solid bitumen (the “tar”). This material is “upgraded” to form synthetic crude, which can be moved by pipeline, in rail cars or highway trucks. Pipeline is by far the cheapest and safest mode of transport.
Once it arrives in a refinery, crude petroleum is heated to boiling and separated into “fractions” with specific boiling ranges for gasoline, diesel fuel, heavy fuel oil and lubricating oil. The (asphalt) residue is used to pave roads and weatherproof flat roofs.
Petroleum refineries can “crack” the heavy fractions, converting high boiling-point hydrocarbons into lighter, more valuable products. Polyunsaturated hydrocarbons and aromatic ring molecules (some are carcinogens) can be hydrogenated into linear or branched molecules. Diesel fuel is predominantly linear while gasoline is made of low boiling-point, branched molecules. How much of each type a refinery produces depends on market demand.
Refineries are powered by their least valuable products. The asphalt may be burned for the heat needed to operate the fractionating columns. Methane is usually sent down pipelines where we burn it to heat our houses. Propane is captured, bottled and sold for barbecues.
Refineries also produce industrial solvents like toluene, mineral spirits, ethylene glycol or butyl acetate. Little is wasted, although some remote refineries “flare” (burn uselessly) surplus methane.
Gaseous fuel, largely methane, is moved inland by pipeline. It can be liquified by cooling to minus-162 Celsius. This liquid natural gas (LNG) is stored in huge insulated tanks and transported by ship. LNG evaporates so rapidly, spills require no “cleanup”; rapid evaporation makes cleanup impossible.
However, spills create an extreme fire hazard. Propane is transported as a liquid under pressure, and sold in the familiar “bottles” which fuel our barbecues. Like LNG, propane spills evaporate so rapidly (boils at minus-42 C), that cleanup is not possible.
Liquids like gasoline, diesel fuel, kerosene (jet fuel) and heating oil are generally moved by pipeline.
However, they are also moved by rail cars and tanker truck. Spills of liquid fuels must be contained by berms and then cleaned up rapidly to avoid contaminating surface waters (lakes, rivers, shallow aquifers). Gasoline spills are highly flammable, complicating cleanup. Diesel or kerosene spills are combustible, but hard to ignite. Fire precautions must still be taken.
Gasoline evaporates rapidly, so spills are usually short-lived, particularly in summer. Diesel fuel and kerosene are slower to evaporate. If cleanup procedures are mounted to remove most of a spill, in summer evaporation quickly remove any residue. In winter, evaporation is slower – perhaps zero if snow covered – and
spill residues may linger until summer comes.
The “bottom line” is always the same. It is far easier and cheaper to take precautions against spilling than it is to clean up a spill!
Peter Bursztyn is a self-proclaimed “recovering scientist” who has a passion for all things based in science and the environment. The now-retired former university academic has taught and carried out research at universities in Africa, Britain and Canada. As a member of BarrieToday's community advisory board, he also writes a semi-regular column. If you have a question Peter might be able to answer or something you're curious about, email us at [email protected].
