Sand and Salt Science: Sand Up Against Snow A-salt (Post #3)

    Salt: the bane of our shoes in Canadian winters. But did you know that the salt used on our roads and sidewalks is carefully measured and mixed by professionals? The article "The perfect mixture: the science of salting, sanding roads", released by The Record News, explains how and why it's important. In school, we've recently learned that the quantity of certain chemicals can have a huge effect on  reaction or physical change. One limiting reagent is always present, a chemical or substance that is used up, thereby stopping the reaction. Carefully measuring these quantities is important, to assure that a reaction does not spiral out of control. Balancing chemical equations can also help understand how much salt is needed when de-icing roads. In this case, a chemical reaction is not exactly taking place, but the melted ice is dissolving the sodium chloride. Water with dissolved salt has a lower freezing point, so the ice takes longer to freeze, or never does.

    The article explains how different cities and towns use different ratios of sand to salt in their mixes. In colder temperatures, more salt must be used, as preventing refreezing is key. But in cities where the temperature is too low for salt to be of any use, more sand is used to provide traction. However, the cities often fail to consider the environmental impact of the salt they are using. A spokesperson for the New York State Department of Environmental Conservation says that when salt is put on roads, it "impacts water quality". She goes on to say that, especially in areas around road salt storage piles, waterways are impacted by salt runoff. 

    This is article is very interesting to me, as someone who has to commute for more than an hour to get to school. The safety of cars on roads is extremely important, but so is the local environment. Of course, humans are always going to choose the quick fix (salt) over a long-term change (fewer cars perhaps?). Salt seems to be pretty necessary in Canada, but I believe we could definitely improve or at least investigate the impact we are having on our environment when we use it.

    So, my question to all of you is this: Is salt harmless enough to continue to use, or should we investigate alternatives? The cost, ease of use, and impact of any alternative must be considered.

Link to article: http://www.troyrecord.com/general-news/20110123/the-perfect-mixture-the-science-of-salting-sanding-roads