Light Oil Contamination of Water Column

There is a difference between weeks or months, versus years....

This is not to excuse laxity in safety measures, but panic is not often justified.

Whoever did the spill should clean up the mess.

That is not the issue. The radio news interviewed the government Manager of environmental disasters for the area. The company that owned the truck involved in the vehicular crash is doing clean up and probably 10 government inspectors consultants and enviro watchdogs for every clean uip workler is swarming the place. Naturally the police totally blocks off the only road connecting north and south.

And the environtalists are declaring fish stocks will be killed for several years to come. The use of detergents and saponifiers is banned because that will cause oil to clump and sink to the bottom.

When we have a diesel spill from a boat the diesel forms a slick which we are told is often only one molecule thick. So why would a fish swimming a foot below the surface ingest this surface layer. I have also been told that gasoline and light diesel fuel will often evaporate in about a week. Is this also a lie?

The lighter fractions within the petroleum will typically evaporate quickly (weather and temperature dependent) leaving the heavier fractions to begin to mix with the water (emulsify) and increase in density. Eventually, the mix will gain enough density that it can be driven deeper into the water column due to wave or other mechanical actions. A rapid cleanup of the surface oil will minimize this affect.

Fuel spill remediation is an important event. The sooner it is started and the more thoroughly it is completed the better for everyone involved.

That being said; there have been many major spills and many solutions to clean them up. Some solutions they conduct an insitu burn where they light the river and burn it away before it can get downstream into larger bodies of water.

Often they try to stop it in rivers with floating berms or if the river is small enough they build an underflow dam where the river is dammed below the spill but the dam is constructed with a pipe through the center of the dam designed to allow subsurface water to pass through but stopping the floating spill and allowing it to collect in quantities that can be easily removed.

Even in rivers where only a fraction was recovered there is hope. There may be a period of time where animals and vegetation die (which is terrible) but it is followed by a period of heavy growth as the oils are broken down and can actually provide some nutrients.

This is the price we pay to have such a cheap dense safe(ish) energy source that can be easily transported across the world. Until we can find a way of harnessing other forms of energy we will be stuck with liquid fuels, fossilized or biodiesel / ethanol.

Fuel companies strive very hard to prevent spills (because it is easier and cheaper than cleaning them) and operators are trained in preventing and stopping spills on a regular basis. Most even conduct simulations so operators can practice their training.

Thank you for the only sensible reply so far. I did not ask advice on what or how to clean up. The accident site was already crawling with clean up crews, Government response management, consultants and enviro watch dogs. Nor was ther any suggestion that the clean-up was going to be difficult or time consuming.

My question was purely about what mechanism is involved in migrating chemicals that float on the surface downward. Your link provided the answer. Light oil such as diesel contain chemical that are soluble in water and by this mechanism some chemicals are drawn down into the water below the surface level. Evidently the other respondents did not read the original post fully. Thanks.

Kramarat is right, do not discount the ability of nature to take care of herself. There are a number of microbes and fungi that LOVE a good diesel fuel meal. Now, cold temps may slow the process down which may be a factor in your locale, but it won't stop it.

My concern with ALL news stories is how many words like "could", "may", "can", "if", "possibly", etc are used. Was the news agency reporting news or selling ad space? -- JHF

This was CBC, the government owned and run broadcast network interviewing a government department manager. CBC does not sell ad space like a commercial service. The point of the story was it would take several years to see if this year's spawning run of Salmon would be affected. Only way to tell is to see how many fish return in 3 years. On the other hand this year we had a bumper crop well beyond the predictions of The fisheries Scientist whose job it is to be knowledgeable about such things.

I understand that air breathing aquatic life or organisms that live in the upper boundary layer are going to be affected. Fingerlings that are spawned in the bottom layer on gravel beds, avoid surface water because that is where predators that feed on these fingerlings are found.

A running river will shift floating oil downstream fairly quickly. Less chance of it ponding and gradually seeping downward in the same place.

This was CBC, the government owned and run broadcast network interviewing a government department manager. CBC does not sell ad space like a commercial service.

They were getting the citizenry primed for some fairly large grants for an "evironmental study" to determne how much damage was done. We have a Hockey team here in South Texas named the "Killer Bees" commemorating the spate of terrorist stories about the "imminent danger" facing us from the Brazilian escape of some African hybrid honeybees several years ago. The construction that resulted at the USDA Research Center at Weslaco is referred to as the "Bee Cathedral" by the locals. The volatility and monomolecular film have already been covered. None of the CBC personnel have ever seen the inside of a chemistry lab, and the department manager is more than willing to sacrifice science to protect his budget. FYI, I was employed at that station for several years after I got my BS in Chemistry.