DISCUSSION
The raised levels of sodium and chloride in every sample give probable reason to believe it is the distribution of salt on the roads that is primarily contaminating the earth surrounding. The increase of sodium and chloride may not be related to the level of traffic volume of the area from which the sample was collected, but if it were it would be that soil surrounding lower vehicular traffic areas contain more salt than higher traffic areas. The best assumption to be made by comparing the samples to each other is that Edgewood parking lots and campus streets are receiving extremely destructive amounts of salt in the winter months. Not only should Edgewood de-icing practices be drastically adjusted, but it may also be wise to seek salt clean-up methods. The Edgewood rain garden post-snow data suggests that the salt is due to parking lot runoff as the outer edges of the garden contain the highest contaminated soil, as where the contamination lessens deeper into the garden (however the levels are still considered "Very High"). The sample of sand used for testing is considered a salt-sand mixture and is offered to the general public for use in the winter months, as well as used by the city. This may not be a very good find, because it is not likely that it is understood that the mixture is really 76 percent salt and may be over-used.
Possible errors may exist: the soil samples may not accurately represent the population, sodium concentrations were calculated based on the chloride concentrations, not measured independently, and we have not accounted for the earth's natural ability to eliminate the concentrations of certain excess elements. This data supports the notion that salt used as a deicer on winter roads is harmful to the environment and all that lives here. As alternatives do exist, their implications need to be researched. Some research has been done on the affects of salt alternatives, yet it is not very developed. Costs are the biggest barrier between salt and an alternative; however no data exists comparing over all and extended economic requirements of various alternatives as compared to those of road salt. Sodium and chloride concentrations are on the rise and are on the way to destroying our watershed; alternative substances and procedures need to be utilized.